A comparison of magnetic resonance imaging and arthroscopic evaluation of chondral lesions of the knee

Correlation of preoperative CT imaging shift parameters of the lateral plateau with lateral meniscal injury in Schatzker IV-C tibial plateau fractures

BACKGROUND

Schatzker IV-C is a high-energy tibial plateau fracture often accompanied by lateral meniscus injuries. While imaging examinations are routine preoperative measurements, the correlation between CT imaging shift parameters of the lateral plateau and lateral meniscal injury in Schatzker IV-C fractures remains uncovered.

METHODS

This retrospective study enrolled a total of 60 patients with Schatzker IV-C tibial plateau fractures at the First People's Hospital of Hefei. Prior to surgery, CT imaging was used to measure the numerical values of lateral plateau depression (LPD) and lateral plateau widening (LPW). The degree of lateral meniscus injury was confirmed based on intraoperative direct vision, with patients being classified into meniscus injury and non-meniscus injury groups. Dichotomous logistic regression was employed to evaluate the correlation between LPD, LPW, and lateral meniscus injury, while the optimal cut-off points for predicting lateral meniscal injury with LPD and LPW were determined using receiver operator characteristic (ROC) curves.

RESULTS

The meniscus injury group exhibited a mean LPD of 15.3 ± 3.5 mm, which was significantly higher than the non-meniscus injury group's mean LPD of 8.4 ± 3.4 mm (P < 0.05). Similarly, the meniscus injury group had a larger mean LPW of 9.4 ± 1.8 mm compared to the non-meniscus injury group's mean LPW of 6.9 ± 0.9 mm (P < 0.05). The optimal cut-off points for predicting lateral meniscal injury were determined to be 8.40 mm for LPD (with a sensitivity of 95%, specificity of 85%, and AUC of 0.898) and 7.90 mm for LPW (with a sensitivity of 75%, specificity of 90%, and AUC of 0.897).

CONCLUSIONS

Patients with Schatzker IV-C tibial plateau fractures are at a significantly higher risk of lateral meniscal injury when the LPD exceeds 8.40 mm and/or the LPW exceeds 7.90 mm. Our results may provide novel reference metrics for the early diagnosis of lateral meniscal injury in Schatzker IV-C tibial plateau fracture patients when the MRI examination is not available.

The clinical utility and diagnostic performance of magnetic resonance imaging for identification of early and advanced knee osteoarthritis: a systematic review

BACKGROUND

Current diagnostic strategies for detection of structural articular cartilage abnormalities, the earliest structural signs of osteoarthritis, often do not capture the condition until it is too far advanced for the most potential benefit of noninvasive interventions.

PURPOSE

To systematically review the literature relative to the following questions: (1) Is magnetic resonance imaging (MRI) a valid, sensitive, specific, accurate, and reliable instrument to identify knee articular cartilage abnormalities compared with arthroscopy? (2) Is MRI a sensitive tool that can be utilized to identify early cartilage degeneration?

STUDY DESIGN

Systematic review.

METHODS

A systematic search was performed in November 2010 using PubMed MEDLINE (from 1966), CINAHL (from 1982), SPORTDiscus (from 1985), SCOPUS (from 1996), and EMBASE (from 1974) databases.

RESULTS

Fourteen level I and 13 level II studies were identified that met inclusion criteria and provided information related to diagnostic performance of MRI compared with arthroscopic evaluation. The diagnostic performance of MRI demonstrated a large range of sensitivities, specificities, and accuracies. The sensitivity for identifying articular cartilage abnormalities in the knee joint was reported between 26% and 96%. Specificity and accuracy were reported between 50% and 100% and between 49% and 94%, respectively. The sensitivity, specificity, and accuracy for identifying early osteoarthritis were reported between 0% and 86%, 48% and 95%, and 5% and 94%, respectively. As a result of inconsistencies between imaging techniques and methodological shortcomings of many of the studies, a meta-analysis was not performed, and it was difficult to fully synthesize the information to state firm conclusions about the diagnostic performance of MRI.

CONCLUSION

There is evidence in some MRI protocols that MRI is a relatively valid, sensitive, specific, accurate, and reliable clinical tool for identifying articular cartilage degeneration. Because of heterogeneity of MRI sequences, it is not possible to make definitive conclusions regarding its global clinical utility for guiding diagnosis and treatment strategies.

CLINICAL RELEVANCE

Traumatic sports injuries to the knee may be significant precursor events to early onset of posttraumatic osteoarthritis. Magnetic resonance imaging may aid in early identification of structural injuries to articular cartilage as evidenced by articular cartilage degeneration grading.

[Arthroscopy prior to osteotomy in cases of unicondylar osteoarthritis]

BACKGROUND

Osteotomy around the knee is an established procedure in orthopaedic surgery. However, there is no consensus regarding whether the patient should have arthroscopy prior to osteotomy in the same operative session.

PATIENTS AND METHODS

This prospective study included 300 cases of osteotomy around the knee with routine arthroscopy. During arthroscopy, the indication for osteotomy was checked first. Then the cartilage status was determined to modify the type and degree of osteotomy correction accordingly. Finally, therapeutic procedures were performed in cases of intraarticular pathology.

RESULTS

The indication for osteotomy was rejected in 51 cases because of worse cartilage status than expected. Twelve patients received immediate or early endoprosthetic treatment. In 208 cases, the degree of correction was modified, in five cases at the level of the osteotomy. For the 288 nonendoprosthetic sessions, there were 268 arthroscopies with therapeutic treatments.

CONCLUSION

This study demonstrated that arthroscopy is indispensable for checking the indications for osteotomy, modifying the type and degree of correction, and performing therapeutic procedures.

Arthroscopy prior to osteotomy around the knee?

INTRODUCTION

Osteotomy around the knee is well established in orthopaedic surgery in cases of congenital/posttraumatic leg deformities with mono-compartment osteoarthritis of the knee. However, there is no consensus whether there should be an arthroscopy prior to osteotomy in the same operative session, either for diagnostic or therapeutic reasons.

PATIENTS AND METHODS

This prospective study included 340 cases of osteotomy around the knee with a routine arthroscopy. During arthroscopy indication for osteotomy was checked first. Then cartilage status was determined to modify type and degree of correction osteotomy accordingly. Finally therapeutic procedures were performed in cases of intraarticular pathologies.

RESULTS

Indication was rejected in 47 cases with ten patients receiving endoprosthetic treatment. In 157 cases the degree of correction was modified, in eleven cases the level of osteotomy. Under the 330 non-endoprothetic sessions there were 316 arthroscopies with therapeutic treatments.

CONCLUSION

This study could demonstrate that arthroscopy in the same session is indispensable, to check the indication for osteotomy, to modify type and degree of correction according to cartilage status and to perform therapeutic procedures.

SPECT scan is a reliable tool for selection of patients undergoing unicompartmental knee arthroplasty

PURPOSE

Was to determine the relationship between pre-operative SPECT and intra-operative assessments of tibio-femoral chondral changes.

METHODS

One hundred cases had been selected on the following criteria: (1) marked Tc-99 m uptake on the medial compartment and (2) its normal uptake laterally. The cartilage macroscopic condition of tibio-femoral compartments were then recorded during the surgery.

RESULTS

A total of 73% of Grade 0, 24% of Grade I, and 3% of Grade II chondral injuries were detected laterally; 100% of Grade IV chondral lesions were detected medially. Statistically very significant relationship was demonstrated between SPECT and the mcroscopic cartilage condition.

CONCLUSIONS

SPECT bone scan provides very useful information regarding the degree of osteoarthritis in knee weight-bearing compartments for pre-operative planning.

Diagnostic procedures and surgical treatment of craniodorsal coxofemoral luxation in calves

OBJECTIVE

To report use of ultrasonographic examination of the coxofemoral joint, a surgical technique for repair of craniodorsal coxofemoral dislocation, and outcome.

STUDY DESIGN

Clinical case reports.

ANIMALS

Calves (n=4) with coxofemoral luxation.

METHODS

Craniodorsal coxofemoral luxation was diagnosed by physical examination, radiographic, and ultrasonographic findings. Open surgical reduction of the femoral head was performed using a modified caudal approach.

RESULTS

Craniodorsal luxation of the femoral head and the presence of an intact femoral neck were confirmed by ultrasonography. All luxations were successfully reduced and reluxation did not occur. At follow-up, 1 heifer had calved and 1 was 5 months pregnant. One calf died of bronchopneumonia 6 days after surgery. One calf had severe coxofemoral degenerative joint disease diagnosed (ultrasonography, radiography, and arthrocentesis) 3 months after surgery and confirmed by necropsy.

CONCLUSION

Ultrasonography proved to be a simple and effective non-invasive technique for diagnosis of coxofemoral luxation. Immediate surgical intervention in hip dislocation in calves is necessary to avoid unnecessary trauma to subchondral structures. In calves, open instead of closed surgical reduction appears preferable because it allows access to the acetabular cavity for removal of debris.

CLINICAL RELEVANCE

Ultrasonography should be considered a supplementary but not an alternative to radiographic examination for diagnosis of coxofemoral luxation and for follow-up examinations after reduction.

Subchondral and trabecular bone remodeling in canine experimental osteoarthritis

INTRODUCTION

We wanted to test the hypothesis that quality changes occur in early-stage arthritic subchondral cancellous bone after acute subchondral damage. So far, not much attention has been paid to changes of the subchondral bone after traumatic subchondral lesions.

MATERIALS AND METHODS

With an established animal model, we produced pure subchondral damage without initial affection of the articular cartilage in 12 Beagle dogs under MRI and histological control. We utilized bone histomorphometry to evaluate bone turnover, its structure and the articular cartilage 6 months after the initial damage.

RESULTS

On follow-up, bone remodelling was indicated, e.g. by a significant increase in the trabecular bone volume and thickness, osteoblast number and osteoid surface and a decrease in the trabecular number in all 12 samples. Several other parameters showed a tendency, e.g. osteoblast surface and osteoclast number. Cartilage analysis showed degenerative changes in ten of 12 samples that had not shown any evidence of damage during the initial examination.

DISCUSSION

Our investigation indicates a significant deterioration in the architecture of the cancellous bone with degenerative changes of the overlying articular cartilage after subchondral lesions, which change the mechanical properties.

Sensitivity of routine 1.0-Tesla magnetic resonance imaging versus arthroscopy as gold standard in fresh traumatic chondral lesions of the knee in young adults

PURPOSE

The purpose of this study was to evaluate the sensitivity, specificity, and accuracy of routine 1.0-Tesla magnetic resonance imaging (MRI) versus arthroscopy in detecting fresh traumatic chondral lesions of the knee.

METHODS

Over a period of 6 years, 578 consecutive military personnel underwent MRI before arthroscopy of the knee. Of these, 32 patients with arthroscopically proven fresh traumatic chondral lesions of the knee were chosen for further analysis. A supplementary condition was that arthroscopy was performed no later than 6 weeks after the onset of trauma. The original MRIs and hospital records were re-evaluated and the chondral lesions were graded and compared with arthroscopic findings. The arthroscopic results served as the gold standard when the sensitivity, specificity, and accuracy of MRI were calculated.

RESULTS

The age of the patients ranged from 19 to 21 years (mean, 19.6 years). MRI detected cartilage defects with a sensitivity of 36% (95% confidence interval [CI], 23% to 50%), specificity of 91% (95% CI, 85% to 95%), and diagnostic accuracy of 78% (95% CI, 72% to 83%). MRI results were affected by the grade of the chondral lesions.

CONCLUSIONS

This study shows that routine 1.0-T MRI is not sensitive but is specific and somewhat accurate in detecting fresh traumatic articular cartilage lesions. The hypothesis of this study was that 1.0-T MRI could replace diagnostic arthroscopy in the diagnosis of fresh traumatic chondral lesions. Our results fail to support this hypothesis because of the poor sensitivity obtained with MRI.

LEVEL OF EVIDENCE

Level II, development of diagnostic criteria.

Radiographs are not useful in detecting arthroscopically confirmed mild chondral damage

Preoperatively predicting chondral damage is important. Weightbearing radiographs, including the standing anteroposterior and 45 degrees flexion posteroanterior views traditionally have been used for this purpose. We wanted to determine if one radiograph had superior sensitivity or specificity in detecting arthroscopically confirmed Grade II chondromalacia (mild arthritis). A standard prospective standing radiographic protocol was designed for all patients who presented to a sports medicine center with knee complaints. Patients who had subsequent arthroscopic surgery had their radiographs measured in a blinded manner for articular cartilage intervals in millimeters to detect joint-space narrowing. Intraarticular chondral damage was correlated with the radiographic findings. Three hundred forty-nine of a possible 411 (87%) patients during a 2-year period had both radiographs and subsequent arthroscopic grading of chondromalacia. This has been the largest study that correlated arthroscopic chondromalacia grades with two commonly preferred weightbearing radiograph projections. Despite specificities greater than 90%, the sensitivity was extremely low and neither standing radiograph was superior. Neither radiograph was useful in detecting Grade II chondral damage.

LEVEL OF EVIDENCE

Diagnostic study, Level I-1 (testing of previously developed diagnostic criteria in series of consecutive patients--with universally applied reference "gold" standard). See the Guidelines for Authors for a complete description of levels of evidence.

MR imaging of post-traumatic articular cartilage injuries confined to the femoral trochlea. Arthroscopic correlation and clinical significance

OBJECTIVE

To assess and describe post-traumatic articular cartilage injuries isolated to the trochlear groove and provide insight into potential mechanism of injury.

MATERIALS AND METHODS

We retrospectively evaluated MR imaging findings of all knee MRIs performed at our institution over the last 2 years (2450). Thirty patients met the criteria of a cartilage injury confined to the trochlear groove. In 15 cases, which were included in our study, arthroscopic correlation was available. Each plane was evaluated and graded for the presence and appearance of articular cartilage defects using a standard arthroscopic grading scheme adapted to MR imaging. Any additional pathological derangement was documented and information about the mechanism of injury was retrieved by chart review.

RESULTS

In all cases the cartilaginous injury was well demonstrated on MRI. In 13 patients additional pathological findings could be observed. The most frequently associated injury was a meniscal tear in nine patients. In eight cases, the arthroscopic grading of the trochlear injury matched exactly with the MRI findings. In the remaining seven cases, the discrepancy between MRI and arthroscopy was never higher than one grade. In 13 out of 15 of patients trauma mechanism could be evaluated. Twelve patients suffered an indirect twisting injury and one suffered a direct trauma to their knee.

CONCLUSION

The findings of this study demonstrate that MR imaging allows reliable grading of isolated injury to the trochlear groove cartilage and assists in directing surgical diagnosis and treatment. These injuries may be the only hyaline cartilage injury in the knee and meniscal tears are a frequently associated finding. Therefore, it is important to search specifically for cartilage injuries of the trochlear groove in patients with anterior knee pain, even if other coexistent pathology could potentially explain the patient's symptoms.

An experimental canine model for subchondral lesions of the knee joint

Aim of the study was to create an animal model for the investigation of the role of subchondral bone damage without initial cartilage lesion in the pathogenesis of osteoarthritis, the mechanical properties of the joints as well as its role in cartilage metabolism. Therefore, after cadaver studies an animal model was created to apply a transarticular load to the femoro-patellar joint under reproducible conditions and produce a pure subchondral damage without affecting the articular cartilage. Following the cadaver studies a first group of four dogs was impacted to identify forces to produce isolated subchondral fractures in the femoral condyle. Then a second group of 12 dogs knee joints was impacted under identical conditions with forces of approximately 2100 N to produce similar subchondral fractures without cartilage damage in one joint under MRI control: T1-weighted SE-sequences. T2-weighted TSE, fat suppressed TIRM-sequences and 3D-FLASH fat saturated sequences. FLASH 3D-sequences revealed intact cartilage after impact in all cases and TIRM-sequences showed subchondral fractures representing bleeding, microfractures and fragmented bone trabecules. Turbo spin echo sequences and T1-weighted images revealed other intact intraarticular structures such as ligaments and menisci. The proposed experimental animal model is suitable to investigate the effect of pure subchondral damage on the articular cartilage and on means of treatment of cartilage defects without surgical intervention and without initial cartilage damage.