Long-term follow-up and survival of delayed total hip arthroplasty following acetabular fracture: a matched cohort study of 552 cases from the Norwegian Arthroplasty Register.

BACKGROUND: Operative treatment of acetabular fractures generally yields good results, but several authors report up to 15-20% of patients developing post-traumatic osteoarthritis (OA). Previous studies have shown that total hip arthroplasty (THA) following post-traumatic OA have inferior results compared to THA for primary OA. The aim of this study was to report on long-term outcome of THA following acetabular fracture, compared to primary OA. MATERIALS AND METHODS: We performed a matched cohort study with data from the Norwegian Arthroplasty Register (NAR). All patients receiving THA following an acetabular fracture between 1987 and 2018 were identified. A 3:1 matched cohort consisting of patients treated for primary OA with THA was selected using propensity scores and matched for age, gender and year of surgery. Survival analysis was performed with revision of any cause as endpoint. Cox regression was used to identify factors associated with risk of revision surgery. RESULTS: 552 cases were identified, 397 men and 155 women. Mean age was 58.8 (11-91) years. 224 had previously been operated for the acetabular fracture, 328 had been treated non-operatively. Mean follow up time was 8.7 (1-29) years. Implant survival at 10 years was 79.7% (75.6-83.3) and at 20 years 62.4% (55.5-69.3). The hazard ratio for revision was 1.38 (1.07-1.77, p < 0.001) compared to the OA cohort, regardless of operative or non-operative treatment of the index acetabular fracture. Uncemented acetabular components had an increased risk of revision with hazard ratio for revision 1.61 (p = 0.012). CONCLUSIONS: THA following an acetabular fracture can be performed with acceptable results regarding implant survival, however, we report an increased risk for revision when compared to primary OA. Our results indicate that previous operative fracture treatment does not increase the risk for THA revision compared to cases treated non-operatively.

Functional outcomes and health-related quality of life after reconstruction of segmental bone loss in femur and tibia using the induced membrane technique.

INTRODUCTION: The induced membrane technique (IMT), frequently called Masquelet technique, is an operative, two-staged technique for treatment of segmental bone loss. Previous studies mainly focused on radiological outcome parameters and complication rates, while functional outcomes and health-related quality of life after the IMT were sparsely reported. MATERIALS AND METHODS: Retrospective study containing of a chart review as well as a clinical and radiological follow-up examination of all patients treated with the IMT at a single institution. The clinical outcomes were evaluated using the Lower Extremity Functional Scale (LEFS), the Short-Form-36 (SF-36) and the visual analog scale (VAS) for pain. The radiographic evaluation contained of standard anteroposterior and lateral, as well as hip-knee-ankle (HKA) radiographs. RESULTS: Seventeen patients were included in the study. All had suffered high-energy trauma and sustained additional injuries. Ten bone defects were localized in the femur and seven in the tibia. Ten patients underwent additional operative procedures after IMT stage 2, among them three patients who contracted a postoperative deep infection. The median LEFS was 59 (15-80), and the SF-36 physical component summary (PCS) and mental component summary (MCS) were 41.3 (24.0-56.1) and 56.3 (13.5-66.2), respectively. The median length of the bone defect was 9 (3-15) cm. In 11 patients, union was obtained directly after IMT stage 2. Bone resorption was observed in two patients. At follow-up, 16 of the 17 bone defects had healed. The median follow-up was 59 months (13-177). CONCLUSION: Our results show a high occurrence of complications after IMT stage 2 in segmental bone defects of femur and tibia requiring additional operative procedures. However, fair functional outcomes as well as a good union rate were observed at follow-up.

Preoperative incipient osteoarthritis predicts failure after periacetabular osteotomy: 69 hips operated through the anterior intrapelvic approach.

BACKGROUND: Untreated developmental hip dysplasia may result in pain, loss of function and is a common cause of osteoarthritis (OA). The periacetabular osteotomy (PAO) was developed to relieve symptoms and postpone further degeneration of the hip. We aimed to assess preoperative clinical and radiographic prognostic factors and evaluate survivorship of PAO after medium-term follow-up of 7.4 (2-15) years. METHODS: 59 patients (69 hips) operated with a PAO through an anterior intrapelvic approach from 1999 to 2011 were retrospectively identified. The patients were evaluated radiographically and clinically with Harris Hip Score, Western Ontario and McMaster Universities Osteoarthritis Index and 15D quality of life questionnaires. Survival analyses identified native hip joint survival predictors. RESULTS: 9 hips (9 patients) were converted to a total hip arthroplasty (THA). Of the 50 remaining patients (60 hips), 44 patients (54 hips) were examined at medium-term follow-up. 3 patients were lost to follow-up or declined participation and 3 were interviewed by telephone. Patient age at time of surgery was 32 (14-44) years. Survival analyses showed 84.3% (95% confidence interval [CI], 68.7-92.5%) survival of the native hip at 8 years follow-up (number at risk 32) (worst case scenario 80% survival at 8 years, 95% CI, 63.9-89.2%, number at risk 32). Cox regression with presence of preoperative OA (Tönnis ⩾1), showed a crude hazard ratio for conversion to THA with preoperative OA of 13.73, p < 0.001. CONCLUSIONS: Periacetabular osteotomy through the anterior intrapelvic approach can be performed safely and with satisfactory results at medium-term follow-up. The presence of preoperative incipient OA (Tönnis ⩾1) is the most important predictor for poor hip joint survival.

Reduced survival for uncemented compared to cemented total hip arthroplasty after operatively treated acetabular fractures.

BACKGROUND: Post traumatic arthritis and avascular necrosis of the femoral head are common complications after operatively treated acetabular fractures. This may cause severe disabilities for the patient, necessitating a total hip arthroplasty. Even though an arthroplasty may provide good symptomatic relief, the long-term results are more uncertain and no consensus exists according to preferred prosthetic designs. With this cohort study, we aimed to investigate the medium to long term arthroplasty survival and clinical results of total hip arthroplasty after operatively treated acetabular fractures. METHODS: We included 52 patients treated with a secondary total hip arthroplasty at a median of 2.4 (0.1-14.1) years after an operatively treated acetabular fracture. The median age was 54 (11-82) years. Cemented arthroplasty was used for 33 patients, 10 patients had an uncemented arthroplasty and 9 patients received a hybrid arthroplasty. Average follow up was 8.0 (SD 5.0) years. RESULTS: Ten-year revision free arthroplasty survival was 79%. Uncemented arthroplasties had a significantly worse 10-year survival of 57%. Arthroplasties performed at a centre without a pelvic fracture service also had a significantly worse 10-years survival of 51%. Cox regression showed similar results with an 8-fold increase in risk of revision for both uncemented arthroplasties and operations performed at a non-pelvic trauma centre. CONCLUSION: Total hip arthroplasty secondary to an operatively treated acetabular fracture provides good symptomatic relief. These patients are, however, complex cases and are probably best treated at specialist centres with both pelvic trauma surgeons and arthroplasty surgeons proficient in complex revisions present.

Long-Term Survival of the Native Hip After a Minimally Displaced, Nonoperatively Treated Acetabular Fracture.

BACKGROUND: Few studies have evaluated the long-term results for nonoperatively treated acetabular fractures. The purpose of this study was to describe the long-term survival of the native acetabulum as well as the clinical and radiographic outcome for patients with nonoperatively treated acetabular fractures. METHODS: All patients with acetabular fractures are prospectively registered in our acetabular fracture database and followed up at regular intervals for up to 20 years. We identified 236 patients (237 fractures) who had been treated nonoperatively between 1994 and 2004; 51 patients with incomplete data were excluded. For the survival analysis, 186 fractures with an average follow-up of 9 years (range, 1 to 20 years) were included. For the long-term clinical outcome, 104 patients with an average follow-up of 12.1 years (range, 9 to 20 years) were included. RESULTS: The 10-year survival of the native hips was 94% (111 hips were at risk). Eighty-nine percent of the patients had a good or excellent Harris hip score, and 88% had a good or excellent Merle d'Aubigné and Postel score. The most important negative predictor for clinical outcome and survival of the hip was a fracture step-off of ≥2 mm measured in the obturator oblique radiograph. CONCLUSIONS: Nonoperative treatment of minimally displaced acetabular fractures yields good to excellent long-term results. For patients with a questionable indication for fracture surgery, oblique radiographs (Judet views) are a helpful tool in the decision-making process, as a fracture step-off of ≥2 mm is a strong predictor for a poor clinical and radiographic result at 10 years. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Patellar resurfacing in total knee arthroplasty: functional outcome differs with different outcome scores: A randomized, double-blind study of 129 knees with 3 years of follow-up.

BACKGROUND AND PURPOSE: Recent research on outcomes after total knee arthroplasty (TKA) has raised the question of the ability of traditional outcome measures to distinguish between treatments. We compared functional outcomes in patients undergoing TKA with and without patellar resurfacing, using the knee injury and osteoarthritis outcome score (KOOS) as the primary outcome and 3 traditional outcome measures as secondary outcomes. PATIENTS AND METHODS: 129 knees in 115 patients (mean age 70 (42-82) years; 67 female) were evaluated in this single-center, randomized, double-blind study. Data were recorded preoperatively, at 1 year, and at 3 years, and were assessed using repeated-measures mixed models. RESULTS: The mean subscores for the KOOS after surgery were statistically significantly in favor of patellar resurfacing: sport/recreation, knee-related quality of life, pain, and symptoms. No statistically significant differences between the groups were observed with the Knee Society clinical rating system, with the Oxford knee score, and with visual analog scale (VAS) for patient satisfaction. INTERPRETATION: In the present study, the KOOS--but no other outcome measure used--indicated that patellar resurfacing may be beneficial in TKA.

Acetabular fracture assessment in four different pelvic trauma centers: have the Judet views become superfluous?

INTRODUCTION: The present study was designed to examine whether oblique radiographs (Judet views) in addition to 2D and 3D CT scans improved the intra- and interobserver reliability when assessing acetabular fractures. MATERIALS AND METHODS: Four international orthopedic pelvic trauma centers reviewed the radiological images for 20 acetabular fracture patients. Three different image sets were made; one set containing plain radiographs including oblique (Judet) views and 2D axial CT scans. The second set contained an AP radiograph of the pelvis, without oblique views, 2D and 3D CT scans. The third set contained all the images. The image sets were evaluated in three separate sessions, for each session the raters were asked to classify the fracture according to Letournel, as well as record a number of other important radiological features concerning the fracture. RESULTS: The interobserver agreement for the Letournel classification was found to be moderate for all image sets. The image set without oblique views showed the best agreement with a kappa value of 0.60. The intra- and interobserver agreement for important modifiers were found to be substantial. The addition of oblique radiographs did not seem to increase the intra- or interobserver agreement for any of the factors evaluated except for the roof arc score. CONCLUSION: The moderate agreement found for the Letournel classification is to be expected given the complexity of the classification. The addition of oblique radiographs to the image sets does not seem to improve the reliability and thus its routine use for classification and decision making may be debated.

The natural history of bone bruise and bone remodelling in the traumatised hip: A prospective 2-year follow-up study of bone bruise changes and DEXA measurements in 13 patients with conservatively treated traumatic hip dislocations and/or fractures.

INTRODUCTION: The purpose of this study was to assess the natural history of bone bruise and bone mineral density (BMD) after traumatic hip dislocations and conservatively treated acetabular fractures. Our hypothesis was that poor bone quality can influence degree of bone bruise and, in time, cause degenerative changes. MATERIALS AND METHODS: Eight consecutive patients with traumatic hip dislocations and five patients with conservatively treated fractures in the femoral head and/or acetabulum were included. Magnetic resonance imaging (MRI) was obtained after 1, 17, 42, 82 and 97 weeks. Dual-emission X-ray absorptiometry (DXA) measurements were made after 10 days and 2 years. Sizes of bone bruise lesions were measured and classified. At the 2-year follow-up, Harris hip score (HHS) was calculated and signs of radiological osteoarthritis (OA) registered. RESULTS: The bone bruise changes were small and all changes resolved within 42 weeks in all, except for three patients; one with a small Pipkin fracture had segmental avascular necrosis (AVN) of the femoral head, one had persisting1-3mm small spots of bone bruises in the femoral head and the third had <1cm lesions in both the femoral head and the acetabulum. The lesions were bigger in the femoral head in the hip dislocations and more pronounced in the acetabulum in the fractured acetabuli. We found no significant changes in BMD in four regions of interest (ROIs) after 2 years. No patients developed OA, and all had excellent HHS except for the one patient with AVN. CONCLUSION: The post-traumatic bone bruise changes in the dislocated hips and the fractured acetabuli were small and transient compared to findings of other authors examining traumatised knees. The patients had excellent function and no OA after 2 years if they did not develop AVN. In our small sample of relatively young patients with normal age-adjusted BMD, no post-traumatic osteopenia was observed. This might differ in the elderly with poorer bone quality; further studies are needed to assess that.

A new method to measure ligament balancing in total knee arthroplasty: laxity measurements in 100 knees.

BACKGROUND: Ligament balancing is considered a prerequisite for good function and survival in total knee arthroplasty (TKA). However, there is no consensus on how to measure ligament balance intra-operatively and the degree of stability obtained after different balancing techniques is not clarified. PURPOSE: This study presents a new method to measure ligament balancing in TKA and reports on the results of a try-out of this method and its inter-observer reliability. METHODS: After the implantation of the prosthesis, spatulas of different thickness were used to measure medial and lateral condylar lift-off in flexion and extension in 70 ligament-balanced knees and in 30 knees were ligament balancing was considered unnecessary. Inter-observer reliability for the new method was estimated and the degree of medial-lateral symmetry in extension and in flexion, and the equality of the extension gaps and flexion gaps were calculated. RESULTS: The method was feasible in all operated knees, and found to be very reliable (intraclass correlation coefficient = 0.88). We found no statistically significant difference in condylar lift-off between the ligament-balanced and the non ligament-balanced group, however, there was a tendency to more outliers in flexion in the ligament-balanced group. CONCLUSIONS: Our method for measuring ligament balance is reliable and provides valuable information in assessing laxity intra-operatively. This method may be a useful tool in further research on the relationship between ligament balance, function and survival of TKA.