Evaluation of a reconstruction reverse shoulder for tumour surgery and tribological comparision with an anatomical shoulder arthroplasty

Electromyographic analysis of selected shoulder muscles during shoulder rehabilitation exercises in patients after reverse total shoulder arthroplasty

BACKGROUND

Reverse shoulder arthroplasty (RSA) aims to restore function in patients with rotator cuff failure and joint arthropathy. After surgery, patients are routinely referred to a rehabilitation specialist to regain range of motion, strength, and function. A key element in these programs is active exercises. The exercises are often selected based on assumed muscle activity, investigated by electromyography (EMG). In particular, in this patient population, activation of the deltoid and the scapular muscles is the focus of exercise therapy. Currently, most studies investigating muscle activity levels during exercises are performed on healthy individuals. To our knowledge, no study exists analyzing EMG activity during exercises in a population of shoulder arthroplasty patients. Therefore, the study aimed to analyze activity in the shoulder girdle muscles during 6 commonly used rehabilitation exercises 12 weeks after reverse shoulder arthroplasty surgery.

METHODS

Forty-four patients (50 shoulders) participated in this cross-sectional study, 12 weeks postoperatively (mean 99.18 ± 12.8 days), aged 68.9 ± 7.75 years. Surface EMG activity was measured in 10 shoulder girdle muscles: the 3 trapezius parts, serratus anterior, the 3 deltoid parts, latissimus dorsi, and 2 pectoralis major parts during 6 exercises, 3 in a closed chain, and 3 open chain elevation exercises.

RESULTS

Gravity-minimized exercises (horizontal plane) show low activity for almost all muscles. Vertical closed kinetic chain exercises show an increased activity compared to horizontal plane exercises. Open kinetic chain exercises against gravity showed the greatest activity in deltoid and upper trapezius. For the other muscles, no consistency in progression was found.

CONCLUSION

This study offers a progression of exercises for patients after reverse shoulder arthroplasty based on increased muscle activity.

Endoprosthetic Reconstruction of the Proximal Humerus with an Inverse Tumor Prosthesis

Reconstructing the proximal humerus after tumor removal is challenging due to muscle and bone loss. The current methods often result in poor shoulder function. This study assessed the long-term functional and oncological outcomes of using an inverse proximal humerus prosthesis in 46 patients with bone tumors. The results showed a mean range of motion of 62° in anteversion, 28° in retroversion, and 55° in abduction. Notably, 23 patients achieved over 90° of shoulder abduction, with an average of 140°. The median Musculoskeletal Tumor Society Score was 25. Complications included infection in two radiotherapy patients and single dislocations in seven patients. One patient with recurrent dislocations needed revision surgery. In conclusion, the use of the inverse proximal humerus prosthesis in bone tumor treatment yields excellent shoulder function and high patient satisfaction. This approach is especially beneficial for those with metastatic disease.

Functional outcome and quality of life following resection of the proximal humerus performed for musculoskeletal tumors and reconstruction done by four different methods

INTRODUCTION

The proximal humerus is a frequent site for both primary and secondary bone tumors. Several options are currently available to reconstruct the resected humerus, but there is no consensus regarding optimal reconstruction. The aim of this retrospective study was to compare the functional outcome, complications and patient compliance following four different types of reconstructive techniques.

MATERIAL AND METHODS

The authors performed 90 proximal humerus resections due to primary and secondary bone tumors over the past 21 years. Four different procedures were performed for reconstruction following the resection: fibula autograft transplantation, osteoarticular allograft implantation, modular tumor endoprosthesis (hemiarthroplasty) and reconstruction of the defect with a reverse shoulder prosthesis-allograft composite. A retrospective analysis of the complications and patient's physical status was performed. Functional outcome and life quality was evaluated by using the MSTS and SF-36 scores.

RESULTS

The best range of motion was observed following arthroplasty with a reverse shoulder prosthesis-homograft composite followed by a fibula autograft reconstruction. Revision surgery was required due to major complications most frequently in the osteoarticular allograft group, followed by the reverse shoulder prosthesis-allograft composite group, the autologous fibula transplantation group; the tumor endoprosthesis hemiarthroplasty group had superior results regarding revision surgery (40, 25, 24 and 14% respectively). MSTS was 84% on average for the reverse shoulder prosthesis-allograft composite group, 70% for the autologous fibula group, 67% for the anatomical hemiarthroplasty group and 64% for the osteoartricular allograft group. Using the SF-36 questionnaire for assessment no significant differences were found between the four groups regarding quality of life.

DISCUSSION

Based on the results of our study the best functional performance (range of motion and patient compliance) was achieved in the a reverse prosthesis-allograft combination group-in cases where the axillary nerve could be spared. The use of an osteoarticular allograft resulted in unsatisfying functional results and high complication rates, therefore we do not recommend it as a reconstructive method following resection of the proximal humerus due to either primary or metastatic bone tumors. Young patients who have good life expectancy but a small humerus or intramedullar cavity reconstruction by implantation of a fibula autograft is a good option. For patients with a poor prognosis (i.g. bone metastases) or in cases where the axillary nerve must be sacrificed, hemiarthroplasty using a tumor endoprosthesis was found to have acceptable results with a low complication rate. According to the MSTS and SF-36 functional scoring systems patients compliance was nearly identical following all four types of reconstruction techniques; the underlying cause may be the complexity of the shoulder girdle. However, we recommend the implantation of a reverse shoulder prosthesis-allograft whenever indication is appropriate, as it has been demonstrated to provide excellent functional outcomes, especially in young adults.

Prosthetic Reconstruction of the Shoulder After Resection of Proximal Humerus Bone Tumor

Prosthetic reconstruction after wide resection of tumors of the proximal humerus presents a unique challenge. The shoulder is a complex articulation, and patients have high expectations for postoperative function. The goal of this study is to compare functional outcomes, oncologic outcomes, and complication rates for 2 reconstructive methods. Forty patients with proximal humeral tumors were reviewed retrospectively. Proximal humeral endoprosthesis (PHE) was used for 21 patients, and reverse shoulder arthroplasty (RSA) was used for 19 patients. Clinical results, oncologic outcomes, and complication rates were assessed. The functional outcomes of the patients were assessed with the Musculoskeletal Tumor Society scoring system (MSTS), the shortened version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) score, and shoulder range of motion. The mean follow-up was 62±15 months. Shoulder dislocations occurred among 8 patients with PHE and 1 patient with RSA (P=.021). The other complication rates were similar for the 2 groups (P<.05). At the latest follow-up, the mean MSTS score was 68±10.3 for those with PHE and 76±7.7 for the patients with RSA (P=.72). However, the QuickDASH score was significantly better (P=.031) for those with RSA (mean, 19±6.3) compared with patients with PHE (mean, 30±4.8). Additionally, shoulder active abduction and forward flexion were significantly greater for the RSA group (P=.04 and P=.03, respectively). Five patients had local recurrence. Prosthetic reconstruction after oncologic re-section of the proximal humerus is associated with significant limitation of shoulder range of motion and a high rate of revision surgery. However, in this study, RSA was associated with fewer dislocations, improved Quick-DASH score, and greater abduction and forward flexion compared with PHE. [Orthopedics. 2022;45(6):e335-e341.].

Implant Survival, Clinical Outcome and Complications of Megaprosthetic Reconstructions Following Sarcoma Resection

Simple Summary

Malignant bone and soft tissue tumors are usually surgically removed with an envelope of healthy tissue as a barrier. If located in the long bones of the upper and lower extremity, this approach leads to a large bone defect commonly affecting a joint. One way to rebuild the bone defect and the neighboring joint is the use of a megaprosthesis that is anchored in the remaining bone comparable to a conventional joint replacement. In general this approach is popular as it provides early stability and allows the affected patient to begin rehabilitation early on. However, complications leading to long-term unplanned reoperation are common. This article provides an overview of current implant survival, types of complication and long-term outcomes of megaprostheses used following tumor resection.

Abstract

Megaprosthetic reconstruction of segmental bone defects following sarcoma resection is a frequently chosen surgical approach in orthopedic oncology. While the use of megaprostheses has gained popularity over the last decades and such implants are increasingly used for metastatic reconstructions and in non-tumor cases, there still is a high risk of long-term complications leading to revision surgery. This article investigates current implant survivorship, frequency and types of complications as well as functional outcomes of upper and lower limb megaprosthetic reconstructions.

The Bateman-Type Soft Tissue Reconstruction around Proximal or Total Humeral Megaprostheses in Patients with Primary Malignant Bone Tumors-Functional Outcome and Endoprosthetic Complications

We aimed to evaluate the functional outcome and endoprosthetic complications following the Bateman-type soft tissue reconstruction around proximal or total humeral replacements in patients undergoing resection of a primary malignant bone tumor. Between September 2001 and December 2018, a total of 102 patients underwent resection of a primary malignant bone tumor and subsequent reconstruction with a modular humeral megaprosthesis in our department. Fifteen (15%) of these patients underwent a Bateman-type soft tissue reconstruction and were included in this retrospective study. The median Musculoskeletal Tumor Society (MSTS) score was 21, the median Toronto Extremity Salvage Score (TESS) was 70, and the median American Shoulder and Elbow Surgeons (ASES) score was 72. Fifty-three percent (8/15) of all patients required a revision surgery after a median time of 6 months. There were 2 soft tissue failures, 3 infections and 3 tumor recurrences. The revision-free implant survivorship amounted to 53% (95% confidence interval (CI) 28-81) after 1 year and 47% (95% CI 22-73) at last follow-up. The Bateman-type reconstruction is a feasible option for soft tissue reconstruction but functional outcome is overall limited and the risk for revision surgery within the first postoperative year is high.

Wear performance of inverted non-conforming bearings in anatomic total shoulder arthroplasty

BACKGROUND

Glenoid component failures still represent the most common complication in total shoulder arthroplasty. These failures depend on several factors, including ultra-high molecular weight polyethylene (UHMWPE) wear. One reason for UHMWPE wear in total shoulder arthroplasty may be the current use of a spherical prosthetic humeral head against a radially mismatched UHMWPE glenoid component, which leads to reduced glenohumeral translations, glenoid edge loading and high translational forces during shoulder motions. The aim of this study was to assess the in vitro wear of an anatomic total shoulder prosthesis with non-spherical non-conforming bearings with inverted conventional materials.

METHODS

The wear of a vitamin E-blended UHMWPE non-spherical humeral head articulating against a non-conforming titanium-niobium nitride (TiNbN)-coated metallic glenoid was tested using a joint simulator. The wear test was performed by applying a constant load of 756 N with angular motions and translations.

RESULTS

After 2.5 million cycles, the mean wear rate of the humeral head was 0.28 ± standard deviation (SD) 0.45 mg/million cycles.

CONCLUSION

The low wear rate of the vitamin E UHMWPE humeral head supports the use of non-spherical non-conforming bearings with inverted conventional materials in anatomic total shoulder arthroplasty.

Clinical, functional and radiological outcomes of extracorporeal irradiation in limb salvage surgery for bone tumours

AIMS

We present a retrospective review of patients treated with extracorporeally irradiated allografts for primary and secondary bone tumours with the mid- and long-term survivorship and the functional and radiographic outcomes.

PATIENTS AND METHODS

A total of 113 of 116 (97.4%) patients who were treated with extracorporeally irradiated allografts between 1996 and 2014 were followed up. Forms of treatment included reconstructions, prostheses and composite reconstructions, both with and without vascularised grafts. Survivorship was determined by the Kaplan-Meier method. Clinical outcomes were assessed using the Musculoskeletal Tumor Society (MSTS) scoring system, the Toronto Extremity Salvage Score (TESS) and Quality of Life-C30 (QLQ-30) measures. Radiographic outcomes were assessed using the International Society of Limb Salvage (ISOLS) radiographic scoring system.

RESULTS

There were 61 (54%) men with a mean age of 22 years (6 to 70) and 52 (46%) women with a mean age of 26 years (3 to 85). There were 23 deaths. The five-year patient survivorship was 82.3% and the ten-year patient survivorship was 79.6%. The mean follow-up of the 90 surviving patients was 80.3 months (2 to 207). At the last follow-up, 105 allografts (92.9%) were still in place or had been at the time of death; eight (7%) had failed due to infection, local recurrence or fracture. Outcome scores were comparable with or superior to those in previous studies. The mean outcome scores were: MSTS 79% (sd 8); TESS 83% (sd 19); QLQ 82% (sd 16); ISOLS 80.5% (sd 19). Pearson correlation analysis showed a strong relationship between the MSTS and ISOLS scores (r = 0.71, p < 0.001).

CONCLUSION

This study shows that extracorporeal irradiation is a versatile reconstructive technique for dealing with large defects after the resection of bone tumours with good functional and radiographic outcomes. Functional outcomes as measured by MSTS, TESS and QLQ-30 were strongly correlated to radiographic outcomes. Cite this article: Bone Joint J 2017;99-B:1681-8.

Silver-coated endoprosthetic replacement of the proximal humerus in case of tumour-is there an increased risk of periprosthetic infection by using a trevira tube?

BACKGROUND AND OBJECTIVES

The aim of our study was to evaluate if there is an increased risk of periprosthetic infection (PJI) in patients following replacement of the proximal humerus by using a modular tumour prosthesis in combination with a trevira tube.

METHODS

Thirty patients were treated by using a modular tumour endoprosthesis (MUTARS®) following intra-articular resection of the proximal humerus. Fifteen patients received treatment by using a trevira tube. In 15 further cases the use of a trevira tube was not necessary. The mean follow-up time was 26 months (range: 24 months to 84 months). Both, Enneking score and range of motion (ROM), was evaluated. Further radiographs were obtained in two planes.

RESULTS

The survival rate one year after surgery was 83 % and 63 % after two years. We recorded a 96 % survival of the limb two years after surgery. We also observed only one case of periprosthetic joint infection (PJI) in the entire follow-up period in one patient who received treatment with a trevira tube. The mean Enneking score was 20 points (range 8 to 26 points). ROM was equal in both study groups. In total 20 % of the treated patients (n = 6) suffered complications.

CONCLUSIONS

Replacement of the proximal humerus by using a trevira tube in combination with a modular tumour endoprosthesis is a safe and viable treatment option for both, bone tumours and metastases. There is no statistically significant increased risk of infection by using trevira tube even among immunosuppressed patients.

LEVEL OF EVIDENCE

Level 3, retrospective comparative study.

Causes of poor postoperative improvement after reverse total shoulder arthroplasty

BACKGROUND

Although reverse total shoulder arthroplasty (RTSA) has been successful in improving pain and function in most patients, some patients fail to improve clinically. The present study used a large registry of RTSA patients to evaluate associations between patient-related factors and poor postoperative improvement after RTSA.

MATERIALS AND METHODS

A prospectively collected shoulder arthroplasty registry was queried for consecutive patients who underwent RTSA from 2007 to 2013. Patients with baseline and minimum 2-year postoperative American Shoulder and Elbow Surgeons (ASES) scores were included. Poor postoperative improvement was defined as a change in the ASES of less than 12 points. Multivariate logistic regression analysis was used to identify independent risk factors.

RESULTS

A total of 150 patients met inclusion and exclusion criteria. Logistic regression revealed that male sex (adjusted odds ratio [OR], 7.9; P = .004), presence of an intact rotator cuff at the time of surgery (adjusted OR, 4.8; P = .025), depression (adjusted OR, 11.2; P = .005), a higher baseline ASES score (P < .001), and higher total number of medical comorbidities (P = .035) were associated with poor postoperative improvement after RTSA.

CONCLUSIONS

Surrogates for better preoperative function after RTSA, such as a higher baseline ASES score and intact rotator cuff at the time of surgery, correlated with poor postoperative improvement. In addition, male sex, depression, and total number of medical comorbidities also correlated with poor postoperative improvement. Interestingly, factors such as patient age and indication for surgery were not found to correlate with poor improvement after RTSA.

Wear simulation strategies for reverse shoulder arthroplasty implants

Reverse total shoulder arthroplasty is a clinically accepted surgical procedure; however, its long-term wear performance is not known. The purpose of this work is to review wear simulator testing of reverse total shoulder arthroplasty, to develop a wear simulator protocol for reverse total shoulder arthroplasty, and to test it by performing a pilot study. The review of wear simulator testing in the literature revealed considerable variation in protocols. A combination of our own cadaveric testing and those of other research groups helped in determining the magnitude and direction of joint loading for the development of the present protocol. A MATCO orbital-bearing simulator was adapted using custom fixtures to simulate a circumduction motion of the shoulder under mildly adverse conditions, and a pilot study gave wear rates within the wide range found in the literature. Arguments were presented in support of the currently developed protocol, but it was also suggested that, rather than rely on one protocol, a series of simulator wear protocols should be developed to fully test the implant wear performance in reverse total shoulder arthroplasty.

Endoprosthetic reconstruction of the proximal humerus after tumour resection with polypropylene mesh

PURPOSE

The purpose of this study was to evaluate the functional outcomes and complications of endoprosthesis-PPP mesh composite reconstruction after bone tumour resection of the proximal humerus.

METHODS

We retrospectively analysed 18 patients treated in our department with endoprosthesis-PPP mesh composite reconstruction after bone tumour resection of the proximal humerus between March 2005 and October 2010. Sixteen patients (16/18) were followed up for 56 months (range, 30-96 months). The pre- and post-operative pain severity was assessed according to a 10-cm visual analogue scale (VAS). The clinical results of functional improvement were assessed by Musculoskeletal Tumour Society (MSTS) score at the time of final follow-up. Moreover, we also analysed complications associated with the reconstruction procedure.

RESULTS

Most patients experienced some alleviation of pain two weeks after the reconstruction surgery. The mean MSTS upper extremity functional outcome score at the time of final follow-up was 20 (66.7 %, range, 16-27). Mean shoulder abduction was 36° (range, 18-125°) and mean shoulder flexion was 39° (range, 21-120°). Local recurrence occurred in only one patient (6.25 %), aseptic prosthesis loosening occurred in one patient (6.25 %) and anterior subluxation occurred in one patient (6.25 %).

CONCLUSIONS

The capsule reconstruction on the basis of PPP mesh can significantly reduce the recurrence rate of glenohumeral joint instability, which may offer an alternative for the capsule reconstruction after bone tumour resection of the proximal humerus.

Improvement of the shoulder function after large segment resection of the proximal humerus with the use of an inverse tumour prosthesis

PURPOSE

Active shoulder function after segmental tumour resection of the proximal humerus and endoprosthetic reconstruction is regularly compromised, while the overall arm function allows a satisfying use in daily activities. The main functional problem remains the loss of huge parts of the shoulder girdle musculature and its bony attachment. In revision arthroplasty inverse shoulder implants can improve the active range of motion significantly in comparison to anatomical shaped prostheses. The aim of this study was to investigate if these promising experiences are transferable to reconstructions after tumour resection of the proximal humerus by using a modular inverse tumour prosthesis.

METHODS

In this study we observed the functional and oncological results of 18 inverse proximal humerus endoprosthetic replacements (IPHP) with the MUTARS system (Implantcast®) after resection of benign (1x giant cell) and malignant (11x primary bone sarcoma, 5x bone metastasis of carcinoma) bone tumours. Mean age at operation was 42 years. The mean postoperative follow-up was 33 months (range ten to 120).

RESULTS

Resection margins were wide in 13 and marginal in five patients. Mean reconstruction length was 15.1 cm (range 6-25 cm). Mean operation time was 191 minutes. The axillary nerve was mostly preserved in 78 % (n = 14). At latest follow-up the patients presented a medium MSTS-score of 24.6/30. The mean active arm abduction in the shoulder joint was 78° and 88° active arm elevation for patients with intact axillary nerve function, but significantly reduced for the four patients with compromised deltoid function. One patient needed a surgical revision due to a deep implant infection.

CONCLUSIONS

The IPHP offers a significant improvement of active shoulder function in patients in whom the axillary nerve can be preserved in comparison to anatomically-shaped implants. However, for patients without any deltoid function there is no benefit regarding an improved active range of motion using an IPHP.

Clinical and radiological outcome of the Total Evolutive Shoulder System (TESS®) reverse shoulder arthroplasty: a prospective comparative non-randomised study

PURPOSE

The aims of this study were to assess the function and quality of life after the Total Evolutive Shoulder System (TESS) reverse shoulder arthroplasty (RSA), to evaluate the radiological stability of the stemless version and to address the effect of arm lengthening and scapular notching (SN) on the outcome.

METHODS

This was a prospective comparative non-randomised study. A total of 37 consecutive patients (40 shoulders) underwent TESS RSA between October 2007 and January 2012; 16 were stemless and 26 were stemmed. At a mean follow-up of 39 months (15-66), we evaluated range of motion (ROM), pain and functional outcome with QuickDASH and quality of life with EQ-5D score. Radiologically, component positioning, signs of loosening, SN and arm length difference were documented.

RESULTS

We found a significant improvement in functional outcome and reduction of pain in both stemmed and stemless groups. No humeral loosening was evident, but there were four glenoid loosenings. In 12 shoulders that developed SN, seven already had scapular bone impression (SBI) evident on initial post-operative radiographs. Glenoid overhang seemed to decrease the risk of SN. Arm lengthening was associated with better EQ-5D but did not influence ROM or functional outcome.

CONCLUSIONS

Reverse shoulder arthroplasty markedly improved shoulder function. SN is of concern in RSA, but proper positioning of the glenoid component may prevent its development.

Complications with reverse total shoulder arthroplasty and recent evolutions

Since its description by Paul Grammont from Dijon, France, several tens of thousands of reverse total shoulder arthroplasties (RTSA) have been performed for diverse conditions. The purpose of this analysis is to identify the complications of this procedure in the literature and in clinical practice. A total of 240 papers concerning RTSA published between 1996 and 2012 have been identified. Over 80 papers describe complications associated with this type of implant. A list of prostheses satisfying European and US standards, CE and FDA approved, has been produced on the basis of information provided by the manufacturers. Data from the literature do not support a meta-analysis. The inventory of best practices shows excellent results in the short and medium term in specific indications, while the number of complications varies between 10 and 65 % in long-term series. Complications can be classified into (A) non-specific including infections (superficial and deep), phlebitis, haematoma, neurological complications of the suprascapular, radial and axillary nerves and (B) specific complications associated with RTSA including (1) on the glenoid side: intraoperative fracture of the glenoid and acromion, late fracture of the scapula, impingement at the scapular neck (notching), glenoid loosening, dissociation of the glenoid component (snatching of the glenosphere) and fractures of the glenoid baseplate; (2) on the humeral side: metaphyseal deterioration, humeral loosening, instability of the shoulder, stiffness with limitation of external and/or internal rotation; and (3) muscular complications with fatty degeneration of the deltoid. Additionally we have identified specific situations related to the type of implant such as the disassembly of the humeral or the glenoid component, dissociation of the polyethylene humeral plate, dissociation of the metaphysis and osteolysis of the tuberosities. The integration of results from different clinical series is difficult because of the lack of a database and the multitude of implants used.