Intraoperative monitoring of the femoral and sciatic nerves in total hip arthroplasty with high-riding 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.

Total hip arthroplasty with subtrochanteric femoral shortening osteotomy using a monoblock cylindrical cementless stem for severe developmental hip dysplasia (Crowe type III, IV)

BACKGROUND

Treatment of patients with Crowe type III and IV dislocated hips is challenging because of the hip deformity in these patients. In addition to the usual total hip replacement, shortening and reduction of the femur are often required. We herein report on our surgical technique using a monoblock cylindrical cementless stem and a direct lateral approach.

METHODS

This study included patients with a diagnosis of severe developmental dysplasia of the hip (Crowe types III and IV) who underwent primary total hip arthroplasty at our hospital from August 2019 to January 2022. Eleven hips of seven patients were treated. All patients underwent horizontal osteotomy using a monoblock cylindrical cementless stem and a direct lateral approach. Complications such as dislocation, infection, and implant dropout were evaluated. In addition, the clinical assessment included the hip range of motion at the last observation and hip function based on the Japanese Orthopaedic Association (JOA) hip score and the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ).

RESULTS

The average operation time was 224 min (range, 194-296 min), and the average bleeding amount was 396.1 g (range, 20-1010 g). The main complications were acetabular implant dislocation, postoperative dislocation, intraoperative arterial injury, intraoperative proximal femoral fracture, subsidence of femoral implant. and postoperative pulmonary infarction, which occurred in one patient each.

CONCLUSION

Total hip arthroplasty for Crowe type III and IV hips is associated with various surgical technical difficulties because of its anatomical characteristics. While patients with severe osteoporosis are contraindicated, the use of a cylindrical monoblock cementless stem and the direct lateral approach makes it possible to simplify the procedure for shortening the femur and increase the indications for surgery.

LEVEL OF EVIDENCE

Therapeutic Level Ⅳ.

Robotic-assisted total hip arthroplasty in patients with developmental dysplasia of the hip

PURPOSES

Due to the morphological diversity of deformities, technical difficulties, improperly designed components, and so on, THA remains a challenging task in dysplastic hips, especially in highly dislocated hips. The purpose of this study was to comprehensively evaluate the clinical outcomes of robot-assisted THA in patients with DDH through a large cohort study, including the precision of acetabular cup positioning, indicators of inflammatory response, indicators of muscle damage, and complications.

METHODS

We retrospectively analyzed patients with DDH who underwent THA in our prospectively constructed joint registry between August 2018 and August 2022. Finally, 147 manual THAs and 147 robotic-assisted THAs were included in the final analysis. Patient demographics, indicators of inflammation, indicators of muscle damage, operative time, Harris hip scores (HHS), and forgotten joint score (FJS) were recorded for analysis. The precision of the positioning of the acetabular component was assessed with plain radiographs.

RESULTS

In the Crowe II/III groups, the reconstructed center of rotation (COR) in the robotic-assisted group was closer to the anatomical COR with less variation than the manual group (absolute horizontal distances of COR 3.5 ± 2.8 vs. 5.4 ± 4.9 mm, p < 0.05; absolute vertical distances of COR 6.4 ± 4.1 vs. 11.7 ± 8.2 mm, p = 0.001). For all Crowe subtypes, the robotic-assisted THA significantly increased the proportion of acetabular cups located in the safety zone within 5° (all p < 0.05). Interleukin-6 and creatine kinase levels were slightly lower and significantly different in the robotic-assisted group at three days postoperatively (all p < 0.05).

CONCLUSIONS

Compared to the manual technique, the robot-assisted technique improved the precision and reproducibility of acetabular component positioning, particularly in DDH patients with Crowe types II/III. The robotic-assisted technique did not increase operative time, bleeding, complications, or revision rates, and had a slighter early inflammatory response and muscle damage.

Intraoperative Neurophysiological Monitoring in Total Hip Arthroplasty for Crowe Types 3 and 4 Hips

Background

Crowe types 3 and 4 dysplastic hips usually need total hip arthroplasty (THA) with femoral shortening osteotomy (FSO) to facilitate reduction, equalize limb length, and decrease the traction stress in nerves. The frequency of peripheral nerve palsy after primary THA has been reported to range from 0.08% to 3.7%. Apart from direct trauma to the nerve, the excessive extension of the extremity is also reported as a common cause of nerve damage. The current study aimed to evaluate the outcomes of intraoperative neurophysiological monitoring (IONM) in THA for Crowe types 3 and 4 hips.

Methods

The data of patients who underwent primary THA with IONM were retrospectively reviewed using our medical records. Patients with Crowe types 3 and 4 dysplastic hips were included in the study. Motor-evoked potentials and somatosensory-evoked potentials were assessed intraoperatively. Preoperative dislocation height and postoperative trochanter minor differences were measured using preoperative and postoperative radiographs.

Results

Twenty-three hips of 19 patients (4 bilateral THAs) with a mean age of 45 years participated in the study. Ten hips (43%) were classified as Crowe type 4, whereas 13 hips (57%) were Crowe type 3. The mean preoperative dislocation height was 41.6 mm (range, 15-100 mm). Postoperatively, only 6 patients had a difference between trochanter minor levels with a mean of 8.5 mm (range, 3-17 mm). Three patients underwent a subtrochanteric FSO to achieve reduction. Postoperatively, no patient had any motor and sensory nerve dysfunction.

Conclusions

According to the results acquired from this study, no nerve palsy was observed after THA for Crowe types 3 and 4 hips, and subtrochanteric FSO was not performed in all Crowe type 3 hips and 70% of Crowe type 4 hips with the aid of IONM.

Peripheral Nerve Blockade in Total Hip Arthroplasty: A Retrospective Study with Propensity Score Matching

The effect of peripheral nerve block (PNB) according to leg lengthening following total hip arthroplasty (THA) has not been studied yet. The purpose of this study was to investigate the effect of PNB according to the change in leg length after THA. From January 2016 to August 2021, 353 patients who underwent unilateral THA for osteonecrosis of the femoral head or osteoarthritis of the hip joint were retrospectively reviewed. The patients were divided into two groups for comparison: 217 patients who controlled postoperative pain using only intravenous venous patient-controlled analgesia (IV PCA) (PCA group) and 136 patients who controlled postoperative pain using PNB and IV PCA (PCA + PNB group). We further divided the patients into two groups (leg lengthening after surgery < 10 mm and >10 mm) and compared them. After propensity score matching, the PCA and PCA + PNB groups, with 134 patients each, were compared and analyzed. The pain intensity at rest was significantly lower in the PCA + PNB group compared with that in the PCA group at postoperative 6, 24, and 48 h (p = 0.0001, 0.0009, and <0.0001, respectively). In the subgroup analysis, for patients whose limb lengthening was less than 10 mm after THA, the pain intensity at rest was significantly lower in the PCA + PNB group compared with that in the PCA group at postoperative 24 and 48 h (p = 0.0165 and 0.0015, respectively). However, in patients whose limb lengthening was more than 10 mm after THA, there was no significant difference between the pain intensity at activity and rest in the two groups at postoperative 6, 24, and 48 h (p > 0.05). PNB did not show superiority in terms of pain reduction in patients whose limb lengthening was more than 10 mm after THA. Further investigations on methods for reducing pain in patients whose leg length is increased by more than 10 mm are needed.

Femoral nerve status during the anterolateral approach for total hip arthroplasty: Motor-evoked potential analysis and an influencing factor

BACKGROUND

Femoral nerve palsy is an uncommon but serious complication during the anterolateral approach for total hip arthroplasty. One of the reported reasons for femoral nerve palsy is retractor-induced intraoperative damage after retractor placement on the anterior wall of the acetabulum. The present study aimed to clarify the femoral nerve status during anterolateral approach total hip arthroplasty using motor-evoked potential analysis and to identify risk factors influencing the nerve status.

METHODS

From June 2019 to September 2020, 32 hips in 31 patients underwent primary total hip arthroplasty via the anterolateral approach. The integrity of the femoral nerve was tested by the motor-evoked potential at three time points: preoperatively as a control (first period), immediately after retractor placement on the anterior wall of the acetabulum (second period), and after the procedure (third period). In the second period, the hips were divided into the following two groups: a <50% femoral nerve amplitude group and a ≥50% group. The iliopsoas muscle volume was evaluated by measuring the muscle cross-sectional area on preoperative computed tomography images, and compared between the two groups.

RESULTS

The mean amplitude of the femoral nerve was significantly reduced from 100% in the first period to 35% in the second period (p < 0.01), but then significantly recovered to 54% in the third period (p < 0.01). In 26 (81%) hips, the femoral nerve amplitude was <50% in the second period. The muscle cross-sectional area of the iliopsoas muscle in the <50% group was significantly smaller than that in the ≥50% group (p < 0.05).

CONCLUSIONS

The mean amplitude of the femoral nerve was significantly reduced to 35% in the second period, and the iliopsoas muscle volume was considered to influence this femoral nerve status.

Neuromonitoring for Proximal Fibular Osteochondroma Excision

BACKGROUND

The peroneal nerve is at risk when excising tumors in the proximal fibula. The rate of nerve injuries during proximal fibular tumor resection varies from 3% to 20%. Our goal was to report our experience with resection of osteochondromas in the proximal fibula and describe the technique and utility of neuromonitoring during excision of proximal fibular osteochondromas (PFO).

METHODS

Patients with a diagnosis of symptomatic PFO who had undergone excision at one institution from 1994 to 2018 were included. An institutional review board-approved retrospective review was performed. Intraoperative neuromonitoring was provided from 2006 on by a single group utilizing a multimodality protocol.

RESULTS

This study contains 29 patients who had excision of osteochondromas in the proximal fibula. Of these 29 consecutively monitored patients, there were 34 involved extremities. Intraoperative neuromonitoring alerts occurred in 10/29 (34.5%) procedures, which included 3 electromyography (EMG) (30%), 2 motor-evoked potential (20%), 1 somatosensory-evoked potential (10%), and 4 alerts with a combination of EMG/motor-evoked potential/somatosensory-evoked potential changes (40%). The interventions that were taken resulted in resolution of the neuromonitoring changes in all procedures. Postoperatively, we noted 2 (6.9%) new mild sensory deficits, which resolved during follow up. There were 3 patients in whom pre-existing sensory-motor deficits improved but not completely after surgery, 1 motor weakness, and 2 with residual paresthesia. In those initially presenting with paresis, there was improvement in 8 of the 8 extremities by the last follow-up visit. Pain as a symptom was resolved in all cases. There were no iatrogenic foot drop injuries. The average follow up was 32.2 months.

CONCLUSIONS

Neuromonitoring during PFO excision demonstrated a high number of alerts, all of which resolved following timely corrective action. The use of neuromonitoring may help decrease the risk of iatrogenic postoperative neurological deficits following fibular osteochondroma surgery.

LEVEL OF EVIDENCE

Level IV.

Does robotic-assisted computer navigation improve acetabular cup positioning in total hip arthroplasty for Crowe III/IV hip dysplasia? A propensity score case-match analysis

AIMS

Total hip arthroplasty (THA) in patients with hip-dislocation dysplasia remains challenging. This study aims to evaluate whether these patients may benefit from robotic-assisted techniques.

METHODS

We reviewed 135 THAs (108 conventional THAs and 27 robotic-assisted THAs) for Crowe type III or IV from January 2017 to August 2019 in our institution. Robotic-assisted THAs were matched with conventional THAs at a 1:1 ratio (27 hips each group) using propensity score matching. The accuracy of cup positioning and clinical outcomes were compared between groups.

RESULTS

The inclination of the cup for conventional THAs and robotic THAs was 42.1 ± 5.7 and 41.3 ± 4.6 (p = 0.574), respectively. The anteversion of the cup for conventional THAs was significantly greater than that of robotic THAs (29.5 ± 8.1 and 18.0 ± 4.6; p < 0.001), respectively. The ratio of the acetabular cup in the Lewinnek safe zone was 37% (10/27) in conventional THAs and 96.3% (26/27) in robotic THAs (p < 0.001). Robotic THAs did not achieve better leg length discrepancy than that of conventional THAs (- 0.4 ± 10.9 mm vs. 0.4 ± 8.8 mm, p = 0.774). There was no difference in Harris Hip Score and WOMAC Osteoarthritis index between groups at the 2-year follow-up. No dislocation occurred in all cases at the final follow-up.

CONCLUSION

Robotic-assisted THA for patients with high dislocation improves the accuracy of the implantation of the acetabular component with respect to safe zone.

[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.

[A study of low back pain and changes in spinal sagittal parameters after total hip arthroplasty in patients with unilateral Crowe type developmental dysplasia of the hip]

Objective

To investigate the changes of low back pain (LBP) and spinal sagittal parameters in patients with unilateral Crowe type Ⅳ developmental dysplasia of the hip (DDH) after total hip arthroplasty (THA).

Methods

The clinical data of 30 patients who met the selection criteria between October 2018 and March 2020 were retrospectively analyzed. Patients were divided into LBP group (16 cases) and control group (14 cases) according to whether there was LBP before operation. There was no significant difference between the two groups of patients in gender, age, body mass index, affected sides, preoperative Harris score ( P>0.05). Full-length lateral X-ray films of the spine were taken within 1 week before operation and at 1 year after operation, and the following imaging indicators were measured: sacral slope (SS), lumbar lordosis (LL ), spinal tilt (ST), spine-sacral angle (SSA), sagittal vertebral axis (SVA). The visual analogue scale (VAS) score, lumbar Oswestry disability index (ODI), the Harris score of the hip joint before operation and at 1 year after operation, and the occurrence of postoperative complications were collected and analysed.

Results

In the LBP group, LBP was relieved to varying degrees at 1 year after operation, of which 13 patients (81.3%) had complete LBP remission; VAS score decreased from 4.9±2.3 preoperatively to 0.3±0.8, ODI decreased from 33.5±22.6 preoperatively to 1.3±2.9, the differences were all significant ( t=7.372, P=0.000; t=5.499, P=0.000). There was no new chronic LBP in the control group during follow-up. The Harris scores of the two groups significantly improved when compared with those before operation ( P<0.05); there was no significant difference between the two groups at 1 year after operation ( t=0.421, P=0.677). There was no significant difference in imaging indexes between the two groups before operation and the difference between pre- and post-operation ( P>0.05). At 1 year after operation, ST and SVA in the LBP group, SSA in the control group, and SS in the two groups significantly improved when compared with those before operation ( P<0.05); there was no significant difference in the other indexes between the two groups before and after operation ( P>0.05).

Conclusion

Unilateral Crowe type Ⅳ DDH patients with LBP before operation were all relieved of LBP after THA. The relief of LBP may be related to the improvement of spinal balance, but not to lumbar lordosis and its changes.

Factors influencing knee valgus alignment in Crowe type IV hip dysplasia after total hip arthroplasty

Background

Valgus deformity of the knee remains a complaint after total hip arthroplasty (THA) among some patients with Crowe type IV hip dysplasia. We aimed to identify the knee alignment in these patients before and after surgery, and to explore the factors contributing to postoperative knee valgus alignment.

Materials and methods

We retrospectively reviewed a series of Crowe type IV patients who received THA between February 2010 and May 2019 in our hospital. The patients’ medical data were collected from the hospital information system. On both preoperative and postoperative full limb length standing radiographs, the following parameters were measured: hip–knee–ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), medial proximal tibial angle, anatomical tibiofemoral angle, anatomical lateral distal femoral angle, femoral neck-shaft angle, pelvic obliquity, limb length, height and lateral distance of hip center, and femoral offset. Univariate and multivariate binary logistic regression were used to identify the factors influencing postoperative knee valgus alignment.

Results

A total of 64 Crowe type IV patients (87 hips) were included in the study. Overall, HKA improved from 176.54 ± 3.52° preoperatively to 179.45 ± 4.31° at the last follow-up. Those hips were subdivided into non-valgus group (≥ 177.0°, n = 65) and valgus group (< 177.0°, n = 22) according to postoperative HKA. Only postoperative mLDFA was a significant factor in the multivariate regression model.

Conclusions

The postoperative mLDFA is a major factor related to knee valgus alignment after THA, which combines the preoperative anatomy and surgical reconstruction. Other factors previously published were found to have no significance.

Level of evidence

III.

Incidence, Injury Mechanisms, and Recovery of Iatrogenic Nerve Injuries During Hip and Knee Arthroplasty

Iatrogenic nerve injury is a rare but potentially devastating complication in total joint arthroplasty of the hip and the knee. Multiple previous studies have evaluated the incidence, mechanisms of injury, recovery, and potential treatments for this complication. Injury in total hip arthroplasty generally involves direct injury of sensory nerves from the incision, direct or traction injury of during exposure, or limb lengthening. Injury in total knee arthroplasty generally involves direct injury of sensory nerves from incision, injury due to errant placement of retractors, during balancing, or from traction because of deformity correction. Treatment of iatrogenic nerve injuries has ranged from observation, intraoperative prevention by nerve monitoring, limb shortening postoperatively, medications, and decompression. The orthopaedic surgeon should be versed in these etiologies to advise their patients on the incidence of injury, to prevent occurrence by understanding risky intraoperative maneuvers, and to select appropriate interventions when nerve injuries occur.

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.

False acetabulum is preoperative guidance for Crowe type IV hips on hip reduction without femoral shortening during total hip arthroplasty

Background

We aimed to analyze if the false acetabulum is a good indicator for determining femoral shortening.

Methods

We retrospectively included 102 patients with unilateral Crowe type IV developmental dysplasia who underwent primary total hip arthroplasty from April 2008 to May 2019. Based on the presence of false acetabulum, the 102 hips were further classified Crowe IVA group and Crowe IVB group. Radiographic measurement included the height of greater trochanter (HGT) preoperatively and postoperatively, which reflected the distalisation of greater trochanter (DGT). Harris hip score (HHS), limb length discrepancy (LLD), and complications were collected as clinical evaluation.

Results

Sixty hips were classified into Crowe IVA group, and 42 hips were classified into Crowe IVB group. Within Crowe IVA group, the proportion of hips treated with subtrochanteric osteotomy was significantly higher than that in Crowe IVB group (97% vs. 12%) (P < 0.001). The DGT in Crowe IVA group was also greater (67 vs. 32 mm) (P < 0.001). At last follow‐up, both two groups obtained excellent clinical scores. There was no significant difference in postoperative LLD between the two groups (P = 0.001). Six dislocations occurred and three patients developed femoral nerve palsy, while all recovered in a year.

Conclusion

The false acetabulum is a promising and good indicator for determining femoral shortening.

The Influence of Femoral Proximal Medullary Morphology on Subtrochanteric Osteotomy in Total Hip Arthroplasty for Unilateral High Dislocated Hips

Objective

To evaluate the predictive values of femoral proximal medullary morphology for the use of subtrochanteric osteotomy (STO) in unilateral Crowe IV developmental dysplasia of the hip (DDH).

Methods

Ninety four patients with unilateral Crowe type IV DDH (59 hips in STO group and 35 hips in the non‐STO group) between April 2008 and June 2019 were enrolled. All patients underwent THA using the Pinnacle acetabular shell, ceramic liner and femoral head, the S‐ROM stem with proximal sleeve. Three parameters on the standard anteroposterior hip radiographs were measured: the widths of medullary canals at 20 mm above the center of lesser trochanter (CLT)，20 mm below the CLT and the isthmus. Canal flare index (CFI), metaphyseal canal flare index (MCFI), diaphyseal canal flare index (DCFI) were calculated. A S‐ROM femoral stem was used in all patients during total hip arthroplasty (THA).

Results

The CFI and DCFI in the STO group were lower than those in the non‐STO group. However, there was no statistical difference in MCFI between the two groups. The receiver operating characteristic (ROC) curves shown that DCFI had the highest area under the curve (AUC), at 0.885. This was followed by the CFI, which had an AUC of 0.847. The AUC of MCFI was 0.579. The optimal threshold for DCFI was 1.44, which lead to a sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 0.771, 0.898, 0.869, and 0.818, respectively. For CFI, the optimal threshold was 3.28, resulting in a sensitivity, specificity, PPV, and NPV of 0.829, 0.729, 0.878, and 0.644, respectively.

Conclusions

The DCFI and CFI may be potent indicators in predicting the use of STO in unilateral Crowe IV DDH. The optimal threshold for CFI and DCFI were 3.28 and 1.44 and had good sensitivity and specificity for predicting the use of STO during THA.

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.

Total Hip Replacement in Developmental Hip Dysplasia: A Narrative Review

The reconstruction of the hip joint in patients suffering from developmental hip dysplasia (DDH) is a demanding procedure and presents many challenges to the reconstructive surgeon. Higher rates of mechanical complications are present in this group of patients. The results of cemented and uncemented implants used in DDH patients are very promising, according to recent outcomes. However, the surgeon has to be aware of several complications, in order to establish an uneventful surgical management of DDH. The specific article investigates the technical challenges and clinical results of total hip arthroplasty in patients with DDH.

Prevalence of combined abnormalities of tibial and femoral torsion in patients with symptomatic hip dysplasia and femoroacetabular impingement

AIMS

The prevalence of combined abnormalities of femoral torsion (FT) and tibial torsion (TT) is unknown in patients with femoroacetabular impingement (FAI) and hip dysplasia. This study aimed to determine the prevalence of combined abnormalities of FT and TT, and which subgroups are associated with combined abnormalities of FT and TT.

METHODS

We retrospectively evaluated symptomatic patients with FAI or hip dysplasia with CT scans performed between September 2011 and September 2016. A total of 261 hips (174 patients) had a measurement of FT and TT. Their mean age was 31 years (SD 9), and 63% were female (165 hips). Patients were compared to an asymptomatic control group (48 hips, 27 patients) who had CT scans including femur and tibia available for analysis, which had been acquired for nonorthopaedic reasons. Comparisons were conducted using analysis of variance with Bonferroni correction.

RESULTS

In the overall study group, abnormal FT was present in 62% (163 hips). Abnormal TT was present in 42% (109 hips). Normal FT combined with normal TT was present in 21% (55 hips). The most frequent abnormal combination was increased FT combined with normal TT of 32% (84 hips). In the hip dysplasia group, 21% (11 hips) had increased FT combined with increased TT. The prevalence of abnormal FT varied significantly among the subgroups (p < 0.001). We found a significantly higher mean FT for hip dysplasia (31°; SD 15)° and valgus hips (42° (SD 12°)) compared with the control group (22° (SD 8°)). We found a significantly higher mean TT for hips with cam-type-FAI (34° (SD 6°)) and hip dysplasia (35° (SD 9°)) compared with the control group (28° (SD 8°)) (p < 0.001).

CONCLUSION

Patients with FAI had a high prevalence of combined abnormalities of FT and TT. For hip dysplasia, we found a significantly higher mean FT and TT, while 21% of patients (11 hips) had combined increased TT and increased FT (combined torsional malalignment). This is important when planning hip preserving surgery such as periacetabular osteomy and femoral derotation osteotomy. Cite this article: Bone Joint J 2020;102-B(12):1636-1645.

One-Stage Total Hip Arthroplasty with Modular S-ROM Stem for Patients with Bilateral Crowe Type IV Developmental Dysplasia

Objective

The aim of the present paper was to evaluate the results of one‐stage total hip arthroplasty (THA) for patients with bilateral Crowe type IV developmental dysplasia of the hip (DDH).

Methods

Data for 58 patients (116 hips) with bilateral Crowe type IV DDH who had one‐stage THA performed by the same surgeon during the period of April 2008 to February 2019 were retrospectively reviewed. The mean age of the patients was 37.3 years; 5 were men and 53 were women. All patients underwent THA through the posterolateral approach using the Pinnacle acetabular cup, a ceramic‐on‐ceramic bearing, and the modular S‐ROM stem. Subtrochanteric shortening osteotomy was performed on 86/116 hips. Intraoperative conditions were recorded. Radiographic and functional outcomes were evaluated, and complications were recorded.

Results

All patients were followed up for an average of 71.3 ± 37.6 months (range, 12–140). The mean operative time was 276.5 ± 57.9 min (range, 175–540). The mean intraoperative blood loss was 933.6 ± 400.8 mL (range, 300–2000). The mean transfusion requirement was 1778 ± 798.0 mL (range, 575–4550). The mean length of hospital stay was 8.6 ± 3.7 days (range, 5–22). At the final follow‐up, no loosening of acetabular and femoral components was observed. No osteolysis and heterotopic ossification occurred. The mean Harris hip scores were improved from 55.4 ± 14.3 preoperatively to 91.3 ± 4.2 postoperatively (P < 0.001) In terms of complications, no perioperative deaths were recorded. Deep vein thrombosis occurred in 1 hip, with no pulmonary embolism. Intraoperative femur fracture occurred in 3 hips, nerve injury in 1 hip, and leg length discrepancy in 1 patient. Postoperative dislocation occurred in 5 hips and nonunion in 1 hip.

Conclusion

Our data demonstrated that one‐stage bilateral THA for bilateral Crowe type IV DDH is feasible and can effectively restore hip function.

Model to Predict Need for Subtrochanteric Shortening Osteotomy During Total Hip Arthroplasty for Crowe Type IV Developmental Dysplasia

Background

Indications for subtrochanteric shortening osteotomy (SSOT) during Crowe type IV developmental dysplasia of the hip (DDH) are unclear. The aim of this retrospective study was to create a model to predict the need for performing SSOT.

Material/Methods

One hundred forty-nine patients (186 hips) with Crowe Type IV DDH who underwent total hip arthroplasty (THA) with S-ROM implants from January 2010 to November 2018 were included in the study. The acetabular components were placed at the true acetabulum and the trial femoral component was inserted. Reduction then was attempted and if it could not be achieved, SSOT was performed. Using multivariable Cox regression analysis, a model was constructed that included age, sex, surgical history, use of a cone- or triangle-shaped sleeve, secondary acetabulum formation, and percentage of dislocation as predictive factors for SSOT.

Results

SSOTs were performed on 140 of 186 hips. Secondary acetabulum formation was present in 27 hips (58.70%) in which SSOT was not performed 7 (5.00%) in which it was performed. Cone-shaped sleeves were used in 17 hips (36.96%) in which SSOT was not performed versus 15 (10.71%) hips in which it was performed. Dislocation occurred in 31.30±5.80% hips in which SSOT was performed versus 24.05±4.39% of those in which it was not performed.

Percentage of dislocation was associated with an increased likelihood of SSOT (odds ratio [OR] 1.24, 95% confidence interval 1.11–1.38), whereas secondary acetabulum formation (OR 0.10, 0.03–0.33) and use of a cone-shaped sleeve (0.18, 0.06–0.53) were associated with decreased likelihood of SSOT. We established a model for prediction of SSOT with a nanogram and the discriminative ability (C statistic) of it was 0.918 (0.79–0.92).

Conclusions

Factors that significantly affect likelihood of performing an SSOT were identified and a model with significant ability to predict the need for SSOT in patients with Crowe Type IV DDH was created.