Crowe Type I and II DDH managed by large diameter metal-on-metal total hip arthroplasty

Are additional screws required for press-fit fixation of cementless acetabular cups? A systematic review and meta-analysis

Background

Press-fit cementless acetabular cup is widely used in total hip arthroplasty (THA). However, the use of additional screws for the acetabular cup has been extensively debated. The purpose of this review is to compare the stability, revision rate, wear rate, and clinical scores of cementless acetabular cups with and without screws in THA.

Materials and Methods

Comprehensive literature searches of the following databases were performed: Cochrane Library, Pubmed, Web of Science, OVID, Elsevier ClinicalKey, Clinicaltrials.gov, and EMBASE. We searched for trials that compared cementless acetabular cups with screws or without screws, and were published in the English language. We evaluated the stability of the prosthesis by osteolysis and migration. The clinical scores included Harris hip scores (HHS) and pain scores.

Results

Nineteen articles involving 4046 THAs met the inclusion criteria. Our analysis revealed that additional screws did not increase the stability of acetabular cups, and there was no statistical significance between the groups with and without screws in osteolysis and clinically relevant migration. Revision rates showed no significant difference between the groups with and without screws. There was no difference in wear between the two groups. Our analysis showed no difference in pain scores and HHS between groups.

Conclusion

Press-fit without screws could achieve sufficient acetabular cup stability. Acetabular cups without screws showed no difference from acetabular cups with screws in many outcomes. Additional screws are not required for cementless acetabular cups.

Level of evidence: Level III.

Total hip arthroplasty for high-riding hips: A retrospective analysis of 79 cases and proposal of a new classification

PURPOSE

Total hip arthroplasty (THA) for high-riding hips is a complex procedure and the requirement for subtrochanteric osteotomy (STO) is an important decision that needs to be taken preoperatively. STO renders this complex surgery even more complicated and there are no guidelines to determine the STO requirement. In this study, the outcomes of THA for patients with high-riding hips were evaluated and a practical classification system is proposed to predict any osteotomy requirement.

METHODS

A retrospective evaluation was made of 79 hips of 76 patients who underwent THA for high-riding hip dysplasia. The amount of shortening in patients with STO and in patients without STO was compared. All patients were evaluated in respect of Harris hip score, operating time, erythrocyte suspension need, and actual limb length discrepancy. Preoperative radiographs were classified into four types according to the ratio of the distance between the lesser trochanter and the ischial tuberosity with pelvic height (LT-IT/P) to grade the degree of dislocation.

RESULTS

The mean follow-up was 30 ± 6.54 months. STO was applied to 47 (60%) hips and not to 32 (40%). There was no statistically significant difference between the groups in respect of the functional scores. STO prolonged the operating time and increased the need for blood transfusion (p = 0.026, p < 0.001, respectively). When the LT-IT/P index was <0.19 (type 1), no additional surgical approach was required for reduction, at 0.19-0.29 (type 2), the head can be safely reduced with additional reduction methods, and when >0.3 (type 3), a shortening osteotomy will most likely be required. The rate of complications is increased if LT-IT/P is >0.4 (type 4).

CONCLUSION

STO adjunct to THA increases the rate of complications. This practical classification system may guide the surgeon in the decision of whether an STO should be added to the procedure or not.

LEVEL OF EVIDENCE

Level III, clinical trial.

Changes in Hip, Knee, and Ankle Coronal Alignments After Total Hip Arthroplasty With Transverse Femoral Shortening Osteotomy for Unilateral Crowe Type IV Developmental Dysplasia of the Hip

BACKGROUND

To investigate changes in lower extremity coronal alignment in patients with unilateral Crowe type IV developmental dysplasia of the hip who underwent total hip arthroplasty with transverse femoral shortening osteotomy.

METHODS

We reviewed the preoperative and 1-year postoperative full-length lower extremity radiographs of 25 patients. Femoral offset (FO), mechanical hip-knee-ankle angle, anatomical axis, mechanical axis deviation (MAD), mechanical lateral proximal femoral angle, anatomical medial proximal femoral angle, mechanical lateral distal femoral angle, anatomical lateral distal femoral angle, knee joint line congruency angle, mechanical medial proximal tibial angle, mechanical lateral distal tibial angle, ankle joint line orientation angle, tibial plafond talus angle, extremity length, and pelvic obliquity were measured on both the operative and nonoperative sides.

RESULTS

Postoperatively, there were significant changes in FO (P = .001), hip-knee-ankle angle (P = .004), MAD (P = .016), mechanical lateral proximal femoral angle (P = .001), anatomical medial proximal femoral angle (P = .012), mechanical lateral distal femoral angle (P = .043), and ankle joint line orientation angle (P = .012) on the operative side. Only MAD (P = .035) changed significantly on the nonoperative side.

CONCLUSION

Modification of FO and reconstruction of hip joint anatomy led to neutralization of knee and ankle valgus alignment. Effects on the nonoperative side were minimal.

Implant survival and patient-reported outcomes after total hip arthroplasty in young patients with developmental dysplasia of the hip

BACKGROUND

Developmental dysplasia of the hip (DDH) is a common cause of hip pain in young patients, and may require treatment with total hip arthroplasty (THA). This study evaluates implant survival and describes patient-reported outcomes after primary THA in DDH patients aged 35 or younger.

METHODS

A retrospective study with prospective follow-up was conducted at a major academic medical centre. Patient charts were reviewed to identify young THA patients with DDH, and follow-up surveys were conducted to determine implant survival and patient-reported outcomes. Kaplan-Meier survival analysis was performed to evaluate implant survival, and the hip disability and osteoarthritis outcome score (HOOS) was used to describe patient-reported outcomes.

RESULTS

This study included 61 patients (75 THAs, 75% follow-up), and the mean time to follow-up was 13 years (range 3-25 years). The 10-year and 20-year implant survival was 87% (95% CI, 78%-94%) and 55% (95% CI, 37%-72%), respectively, and implant survival was significantly better in patients over the age of 25 at the time of surgery (p value &lt;0.01). The mean HOOS patient scores were 83 for pain (SD 20.29), 78 for symptoms (SD 19.72), 83 for ADLs (SD 20.89), and 74 for sports (SD 25.92). Patients that were younger at the time of surgery or required custom implants reported worse HOOS-Symptom scores at follow-up (p value = 0.02).

DISCUSSIONS

Young patients with DDH have good outcomes after surgery. Patient factors and implant characteristics should be considered when predicting implant survival and outcomes after THA in young patients with DDH.

Large-diameter metal-on-metal total hip arthroplasty: dislocation infrequent but survivorship poor

BACKGROUND

Use of large-diameter metal-on-metal (MoM) articulations in THA increased, at least in part, because of the possibility of achieving improved joint stability and excellent wear characteristics in vitro. However, there have been subsequent concerning reports with adverse reactions to metal debris (ARMD), pseudotumors, and systemic complications related to metal ions.

QUESTIONS/PURPOSES

The purpose of this study was to determine at a minimum of 2 years' followup (1) the proportion of patients who experienced a dislocation; (2) the short-term survivorship obtained with these implants; (3) the causes of failure and the proportion of patients who developed ARMD; and (4) whether there were any identifiable risk factors for revision.

METHODS

We reviewed the results of 1235 patients who underwent 1440 large-diameter MoM primary THAs at our institution using two acetabular devices from a single manufacturer with minimum 2-year followup. Large-diameter MoM devices were used in 48% (1695 of 3567) of primary THAs during the study period. We generally used these implants in younger, more active, higher-demand patients, in patients considered at higher risk of instability, and in patients with adequate bone stock to achieve stable fixation without use of screws. Clinical records and radiographs were reviewed to determine the incidence and etiology of revision. Patients whose hips were revised were compared with those not revised to identify risk factors; Kaplan-Meier survivorship analysis was performed as was multivariate analysis to account for potential confounding variables when evaluating risk factors. Minimum followup was 2 years (average, 7 years; range, 2-12 years); complete followup was available in 85% of hips (1440 of 1695).

RESULTS

Dislocation occurred in one hip overall (<1%; one of 1440). Kaplan-Meier analysis revealed survival free of component revision was 87% at 12 years (95% confidence interval, 84%-90%). The two most common indications for revision were ARMD (48%; 47 of 108 hips revised) and loosening or failure of ingrowth (31%; 34 of 108). Risk factors for component revision were younger age at surgery (relative risk [RR] 0.98 per each increased year; p=0.02), higher cup angle of inclination (RR 1.03 per each increased degree; p=0.04), and female sex (RR 1.67; p=0.03).

CONCLUSIONS

Large-diameter MoM THAs are associated with a very low dislocation rate, but failure secondary to ARMD and loosening or lack of ingrowth occur frequently. Patients with MoM THA should be encouraged to return for clinical and radiographic followup, and clinicians should maintain a low threshold to perform a systematic evaluation. Early diagnosis and appropriate treatment are recommended to prevent the damaging effects of advanced ARMD.

LEVEL OF EVIDENCE

Level IV, Therapeutic study.

Nationwide investigation into adverse tissue reactions to metal debris after metal-on-metal total hip arthroplasty in Japan

BACKGROUND

Adverse reactions to metal debris (ARMD) after receiving metal-on-metal (MoM) hip implants is a recent concern. However, no epidemiologic study has examined ARMD for MoM hip implants in Japan. The purposes of this study were to research the incidence of ARMD and to identify poorly performing MoM hip implants in Japan.

METHODS

From 2000 to 2011, 7 companies provided 23,226 MoM implants in Japan. A questionnaire regarding ARMD was sent to 101 hospitals at which 62% of the 23,226 MoM implants had been used.

RESULTS

Replies to the questionnaire were received from 82 hospitals. In these hospitals, surface hip replacement types (SRs) were used in 606 hips and stemmed types were used in 12,961 hips. ARMD were reported in 3 hips (0.5%) with SRs and 160 hips (1.2%) with stemmed types. ARMD in the 3 hips with SRs were asymptomatic and no revisions were performed. Among AMRD with stemmed implants, revision was performed in 83 hips and excision of an ARMD lesion was performed in 3 hips. The remaining 74 hips were asymptomatic and careful follow-up was continued. A significant difference in reoperation rate was evident between SRs (0%) and stemmed types (0.7%). Incidences of ARMD were significantly higher with Ultamet (P = 0.005), Conserve (P < 0.001), and Cormet (P < 0.001) MoM bearing couples than with Metasul bearings.

CONCLUSIONS

The incidence of ARMD in large surgical volume hospitals in Japan from 2000 to 2011 was estimated to be 0.5% with SRs and 1.2% with stemmed types. The reoperation rate was significantly higher with stemmed types than with SRs. Three brands of MoM stemmed implants were identified as showing a higher incidence of ARMD.