[Temporomandibular joint prostheses]

Temporomandibular joint prosthesis. The temporomandibular joint can be affected by end-stage pathology such as arthritic disease, trauma, ankylosis. The main debilitating symptoms results in limited mouth opening and pain. TMJ prosthesis is recommended for disease resulting in an anatomical modification and aims at restoring joint function with pain relief. Despite its initial history of health scandals, prosthetic replacement for end-stage TMJ disease is gradually becoming a common procedure because of good functional results and low morbidity. Significant advances have been made in the design of the temporomandibular joint prostheses during the last decades, specially thanks to the use of 3D printing. The indications should be further clarified and extended.

Reverse shoulder arthroplasty for proximal humerus fractures: Is the glenoid implant problematic?

INTRODUCTION

Reverse shoulder arthroplasty (RSA) is a key tool in the orthopedic trauma surgeon's arsenal, especially when faced with a proximal humerus fracture in older patients. However, few studies have focused on the glenoid side of RSA in this indication as the implant is placed in a generally healthy scapula.

HYPOTHESIS

Glenoid implants for RSA after trauma are well positioned and do not often cause complications.

MATERIAL AND METHODS

Retrospective multicenter study of 513 patients who underwent RSA because of a proximal humerus fracture. The mean follow-up was 55 months. Radiographs were used to assess the height and tilt of the glenoid implant, along with the development of scapular notching or loosening. The clinical outcomes were determined based on the Constant score.

RESULTS

At the last follow-up, 44% of shoulders had scapular notching, 7% of which were severe (stages 3-4). This notching was progressive, with two resulting in loosening. The rate of severe notching was higher in patients with a high glenoid implant (62.5% vs. 42.3%, p=0.03) or glenosphere with superior tilt (58.3% vs. 37.8%, p=0.02). Nine patients had confirmed loosening and 63 had potential loosening. This was more common in cases with superior tilt (9.3% vs. 0.4%, p<0.001). Patients with a high glenoid implant had a lower Constant score (57 vs. 45, p<0.001). There fewer cases of severe notching when a lateralized glenoid implant was used (0% vs. 7%, p<0.05) and/or the humeral implant had a smaller neck-shaft angle (implants<155°: 3% vs. implants at 155°: 8.5%, p=0.03).

DISCUSSION AND CONCLUSION

Glenoid loosening and severe scapular notching are related to poor positioning and/or incorrect orientation of the glenosphere. Implant selection is important, as there is little to no notching when less-angled humeral implants and lateralized glenoid implants are used.

LEVEL OF EVIDENCE

IV.

Deep prosthetic joint infection: a qualitative study of the impact on patients and their experiences of revision surgery

OBJECTIVES

Around 1% of patients who have a hip replacement have deep prosthetic joint infection (PJI) afterwards. PJI is often treated with antibiotics plus a single revision operation (1-stage revision), or antibiotics plus a 2-stage revision process involving more than 1 operation. This study aimed to characterise the impact and experience of PJI and treatment on patients, including comparison of 1-stage with 2-stage revision treatment.

DESIGN

Qualitative semistructured interviews with patients who had undergone surgical revision treatment for PJI. Patients were interviewed between 2 weeks and 12 months postdischarge. Data were audio-recorded, transcribed, anonymised and analysed using a thematic approach, with 20% of transcripts double-coded.

SETTING

Patients from 5 National Health Service (NHS) orthopaedic departments treating PJI in England and Wales were interviewed in their homes (n=18) or at hospital (n=1).

PARTICIPANTS

19 patients participated (12 men, 7 women, age range 56-88 years, mean age 73.2 years).

RESULTS

Participants reported receiving between 1 and 15 revision operations after their primary joint replacement. Analysis indicated that participants made sense of their experience through reference to 3 key phases: the period of symptom onset, the treatment period and protracted recovery after treatment. By conceptualising their experience in this way, and through themes that emerged in these periods, they conveyed the ordeal that PJI represented. Finally, in light of the challenges of PJI, they described the need for support in all of these phases. 2-stage revision had greater impact on participants' mobility, and further burdens associated with additional complications.

CONCLUSIONS

Deep PJI impacted on all aspects of patients' lives. 2-stage revision had greater impact than 1-stage revision on participants' well-being because the time in between revision procedures meant long periods of immobility and related psychological distress. Participants expressed a need for more psychological and rehabilitative support during treatment and long-term recovery.

The Treatment of Joint Pain with Intra-articular Pulsed Radiofrequency

Background

The intra-articular (IA) application of pulsed radiofrequency (PRF) for pain in small and large joints represents a recent development that has proven to be effective in many cases. We performed a retrospective study of 89 such procedures in 57 consecutive patients with chronic articular pain.

Objectives

The aim of this retrospective study is to evaluate the effectiveness of intraarticular PRF in a group of 57 consecutive patients with chronic joint pain.

Patients and Methods

Patients with intractable joint pain for more than 6 months were treated with IA PRF 40-45V for 10-15 min in small joints and 60V for 15 min in large joints using fluoroscopic confirmation of correct needle position. A total of 28 shoulders, 40 knees, 10 trapezio-metacarpal, and 11 first metatarso-phalangeal joints were treated. Results were evaluated at 1, 2, and 5 months. The procedure was repeated after 1 month in 10 patients with initial suboptimal results. Success was defined as a reduction of pain score by at least 50%.

Results

All groups showed significant reductions in pain scores at all three follow-up visits. Success rates were higher in small joints (90% and 82%, respectively) than large ones (64% and 60%, respectively). Interestingly, IA PRF was successful in 6 out of 10 patients who had undergone previous surgery, including 3 with prosthetic joint replacement and in 6 of the 10 repeated procedures. There were no significant adverse effects or complications.

Conclusions

IA PRF induced significant pain relief of long duration in a majority of our patients with joint pain. The exact mechanism is unclear, but may be related to the exposure of immune cells to low-strength RF fields, inducing an anti-inflammatory effect. The success rate appears to be highest in small joints. We recommend additional research including control groups to further investigate and clarify this method; our data suggest that it may represent a useful modality in the treatment of arthrogenic pain.

UPDATE ON INFECTIONS IN ARTICULAR PROSTHESIS

The implantation of joint prostheses, especially for the hip and knee, is becoming increasingly common. This provides a significant reduction in discomfort and an immeasurable improvement in patient mobility. Reviews of the worldwide literature indicate that 1 to 5% of these prostheses become infected, although it is important to remember that as the number of operations performed to implant these prosthesis increases, so will the number of cases of this type of infection. Gram-positive bacteria predominate in contaminations of joint prostheses, in particular Staphylococcus aureus and Staphylococcus epidermidis. Infections caused by gram-negative bacilli and fungi such as Candida sp have been reported with increased frequency throughout the world. Infections of joint prostheses present characteristic signs that can be divided into acute manifestations (severe pain, high fever, toxemia, heat, redness and wound secretions) and chronic manifestations (progressive pain, cutaneous fistula formation and pus drainage, without fever). The definitive diagnosis of the infection should be made through cultures to isolate the microorganism, using material collected from joint fluid puncture, surgical wound secretions, and surgical debridement. It is essential to cover for methicillin-resistant Staphylococcus aureus, given the epidemiological importance of this agent in these infections. The total duration of antibiotic therapy ranges from six weeks to six months, and this treatment should be adjusted as needed, based on the results from culturing.