Periprosthetic humeral fractures: mechanisms of fracture and treatment options

Comparing the Biomechanical Stability of Cerclage Cable with Plate Insert Versus Locking Screw in Periprosthetic Humeral Fracture

BACKGROUND

In the setting of periprosthetic humeral fractures, the humeral stem of the implant represents a substantial challenge to the optimal method of proximal fixation. This study aimed to compare the initial biomechanical stability provided by cerclage cables with a locking plate insert versus bicortical locking screws (i.e., the gold standard for fixation) in fresh cadaveric humeri.

METHODS

After calculating the sample size, we utilized 10 sets of cadaveric specimens and created a 5-mm osteotomy gap 120 mm distal to the tip of the greater tuberosity, simulating a Wright and Cofield type-B periprosthetic humeral fracture on each specimen. Using 3 locking screws for distal fragment fixation, identical in all specimens, the specimens were assigned to Group A (3 cerclage cables with a plate insert) or Group B (3 locking bicortical screws) for proximal fragment fixation. Biomechanical tests included stiffness in varus and valgus bending, torsion, and axial compression, and a single load to failure.

RESULTS

No significant differences were observed in the biomechanical metrics between the 2 groups.

CONCLUSIONS

Our study revealed that fixation with use of cerclage cables with a plate insert demonstrated biomechanical stability comparable with that of bicortical locking screw fixation when addressing the proximal fragment in Wright and Cofield type-B periprosthetic humeral fractures.

CLINICAL RELEVANCE

For proximal fragment fixation of periprosthetic humeral fractures, cerclage cables with a plate insert can be utilized as an effective fixation method that offers initial fixation strength that is comparable to the use of 3 locking bicortical screws.

Time-elapsed microstructural imaging of failure of the reverse shoulder implant

BACKGROUND

Reverse Shoulder Arthroplasties (RSA) have become a primary choice for improving shoulder function and pain. However, the biomechanical failure mechanism of the humeral component is still unclear. The present study reports a novel protocol for microstructural imaging of the entire humerus implant under load before and after fracture.

METHODS

A humerus specimen was obtained from a 75-year-old male donor. An expert surgeon implanted the specimen with a commonly used RSA implant (Aequalis reversed II, Stryker Orthopaedics, USA) and surgical procedure. The physiological glenohumeral contact force that maximized the distal implant migration was selected from a public repository ( orthoload.com ). Imaging and concomitant mechanical testing were performed using a large-volume micro-CT scanner (Nikon XT H 225 ST) and a custom-made compressive stage. Both when intact and once implanted, the specimen was tested under a pre-load and by imposing a constant deformation causing a physiological reaction load (650 N, 10 degrees adducted). The deformation of the implanted specimen was then increased up to fracture, which was identified by a sudden drop of the reaction force, and the specimen was then re-scanned.

RESULTS

The specimen's stiffness decreased from 874 N/mm to 464 N/mm after implantation, producing movements of the bone-implant interface consistent with the implant's long-term stability reported in the literature. The micro-CT images displayed fracture of the tuberosity, caused by a combined compression and circumferential tension, induced by the distal migration of the implant.

CONCLUSION

The developed protocol offers detailed information on implant mechanics under load relative to intact conditions and fracture, providing insights into the failure mechanics of RSA implants. This protocol can be used to inform future implant design and surgical technique improvements.

The Treatment of Periprosthetic Fracture Revision of the Humerus with "Bamboo Support" Structural Allograft Technique-Atrophic Non-Union of a Post-Operative Periprosthetic Fracture after Reverse Total Shoulder Arthroplasty: A Case Report

Periprosthetic fractures are a serious complication of joint replacement surgery. With the growing prevalence of reverse total shoulder arthroplasty (RTSA), the incidence of relatively uncommon periprosthetic humeral fractures has increased. Here, we present the unique case of a 74-year-old woman who developed atrophic non-union after plate osteosynthesis for a periprosthetic fracture associated with RTSA. Fixation failure was evident 3 months after the surgical intervention; the patient underwent a 3-month course of arm sling immobilization. However, bone resorption continued, and varus angulation of the fracture developed. In this case, surgical strategy involved the use of long proximal humerus internal locked system plate (DePuy Synthes, Paoli, PA, USA), augmented with autologous iliac bone graft and allogenic humerus structural bone graft with the "bamboo support technique", fixed with Cable System (DePuy Synthes, Paoli, PA, USA). No reports have addressed the management of failed periprosthetic fractures using allogeneic humeral strut bone grafts. This report aims to fill the gap by presenting a novel surgical technique for the management of periprosthetic fractures associated with RTSA in case of treatment failure.

The effect of shoulder prosthesis stem length on failure due to torsional loading. A biomechanical study in composite humeri

Background

Shoulder arthroplasty is becoming increasingly common. With evolving implant designs, multiple humeral stem options exist for the surgeon to choose from. New stemless and short-stem systems are modular, remove less native bone stock, and better adapt to patient anatomy. It has been suggested that shorter stem implants may be protective against periprosthetic fracture; however, this has not been mechanistically evaluated. Therefore, this study aimed to biomechanically test synthetic humeri with long-stem, short-stem, and stemless arthroplasty components in a torsional manner to evaluate their response to loading and characterize failure.

Methods

Twenty-four synthetic humeri were implanted with long stem, short stem, or stemless uncemented prosthesis, 8 in each group. Humeri were mounted in a custom testing jig with a morse taper interfacing with a mechanical testing system. After a 20N axial force, specimens were torsionally loaded to failure at 15 degrees/sec, with 50 Hz collection. Torque vs. rotation curves were generated for each specimen, and stiffness, yield, ultimate strength, and failure load were measured. ANOVA and post hoc pairwise comparisons were used to assess effect of stem type on mechanical test variable. The association of the stem type with fracture type was analyzed by a Fisher's Exact test. Statistical significance was set at P < .05.

Results

During torsional loading, long-stem implants were significantly stiffer than short or stemless implants. The angle of implant yielding was similar across stem designs; however, stemless implants had a lower yield torque. This correlated with a decreased yield energy in stemless compared to short stems as well. Maximum torque and failure torque was also significantly higher in short-stem and long-stem implants compared to stemless.

Discussion

Periprosthetic fractures in shoulder arthroplasty are a concern in low-energy trauma, and stem design likely plays a significant role in early implant-bone failure. Our results suggest stemless implants under torsional load fail at lower stress and are less stiff than stemmed implants. The failure mechanism of stemless implants through metaphyseal cancellous bone emphasizes the effect bone quality has on implant fixation. There is likely a balance of torsional stability to survive physiologic loads while minimizing diaphyseal stress and risk of diaphyseal periprosthetic fracture. This combined with revision and fixation options represent decisions the surgeon is faced with when performing shoulder arthroplasty.

Incidence of complications related to shoulder arthroplasties identified on computed tomography

PURPOSE

Determine incidence of shoulder arthroplasty complications identified on computed tomography (CT).

MATERIALS AND METHODS

Retrospective institutional database review of patients with shoulder arthroplasties who underwent CT between 01/2006-11/2021 at a tertiary academic referral center with subspecialized orthopedic shoulder surgeons. CT reports were reviewed for arthroplasty type and complication. Data were stratified and summarized. Associations between complications and arthroplasty types were determined with Chi-squared goodness of fit test.

RESULTS

Eight hundred twelve CTs in 797 unique patients were included (438 (53.9%) females and 374 (46.1%) males; mean age 67 ± 11 years). There were 403 total shoulder arthroplasties (TSA), 317 reverse total shoulder arthroplasties (rTSA), and 92 hemiarthroplasties (HA). Complications were present in 527/812 (64.9%) and incidences were: loosening/aseptic osteolysis 36.9%, periprosthetic failure 21.6%, periprosthetic fracture 12.3%, periprosthetic dislocation 6.8%, joint/pseudocapsule effusion 5.9%, prosthetic failure 4.8%, infection 3.8%, and periprosthetic collection 2.1%. Complications per arthroplasty were: 305/403 (75.7%) TSAs, 176/317 (55.5%) rTSAs, and 46/92 (50%) HAs (p < 0.001). Periprosthetic fracture (20.8%), prosthetic dislocation (9.8%), and prosthetic failure (7.9%) were highest in rTSAs (p < 0.001, p < 0.013, p < 0.001, respectively). Loosening/aseptic osteolysis most frequent in TSAs (54.1%) (p < 0.001). Periprosthetic failure most frequent in HA (32.6%) (p < 0.001). Significant associations were identified with joint/pseudocapsule effusion and loosening/aseptic osteolysis (p = 0.04) and prosthetic dislocation (p < .001).

CONCLUSION

In this single tertiary academic referral center cohort, the incidence of shoulder arthroplasty complication identified on CT was 64.9% and the most commonly occurring complication was loosening/aseptic osteolysis (36.9%). TSA had the highest incidence of complication (75.7%).

Inter-Observer and Intra-Observer Reliability Assessment of the Established Classification Systems for Periprosthetic Shoulder Fractures

This study evaluated the reliability and comprehensiveness of the Unified classification system (UCPF), Wright & Cofield, Worland and Kirchhoff classifications and related treatment recommendations for periprosthetic shoulder fractures (PPSFx). Two shoulder arthroplasty specialists (experts) and two orthopaedic residents (non-experts) assessed 20 humeral-sided and five scapula-sided cases of PPSFx. We used the unweighted Cohen's Kappa (κ) for measuring the intra-observer reliability and Krippendorff's alpha (α) for measuring the inter-observer reliability. The inter-rater reliabilities for the Wright & Cofield and Worland classifications were substantial for all groups. The expert and non-expert groups for UCPF also showed substantial inter-rater agreement. The all-rater group for the UCPF and the expert and non-expert group for the Kirchhoff classification revealed moderate inter-rater reliability. For the Kirchhoff classification, only fair inter-rater reliability was found for the non-expert group. Almost perfect intra-rater reliability was measured for all groups of the Wright & Cofield classification and the all-rater and expert groups of the UCPF. All groups of the Kirchhoff and Worland classifications and the group of non-experts for the UCPF had substantial intra-rater reliabilities. Regarding treatment recommendations, substantial inter-rater and moderate intra-rater reliabilities were found. Simple classification systems for PPSFx (Wright & Cofield, Worland) show the highest inter- and intra-observer reliability but lack comprehensiveness as they fail to describe scapula-sided fractures. The complex Kirchhoff classification shows limited reliability. The UCPF seems to offer an acceptable combination of comprehensiveness and reliability.

Periprosthetic fractures: an unrecognized osteoporosis crisis

Total joint replacement is common and increasing. Many of these patients have low bone mineral density preoperatively, and arthroplasty leads to bone loss. As falls are common before and after arthroplasty, it is unsurprising that periprosthetic fractures, defined as those associated with an orthopedic device, whether a joint replacement or other internal fixation devices, are not rare. These fractures engender morbidity and mortality comparable to osteoporosis-related hip fractures but remain largely unrecognized and untreated by osteoporosis/metabolic bone disease clinicians. Indeed, recent osteoporosis guidelines are silent regarding periprosthetic fractures. The purposes of this clinical review are to briefly describe the epidemiology of arthroplasty procedures and periprosthetic fractures, raise awareness that these fractures are osteoporosis-related, and suggest approaches likely to reduce their occurrence. Notably, bone health evaluation is essential following the occurrence of a periprosthetic fracture to reduce subsequent fracture risk. Importantly, in addition to such secondary fracture prevention, primary prevention, i.e., bone health assessment and optimization prior to elective orthopedic procedures, is appropriate.

Evaluation and treatment of postoperative periprosthetic humeral fragility fractures

Postoperative periprosthetic humeral shaft fractures represent a growing and difficult complication to treat given the aging patient population and associated bone loss. Determining the best treatment option is multifactorial, including patient characteristics, fracture pattern, remaining bone stock, and implant stability. Possible treatment options include nonoperative management with bracing or surgical intervention. Nonoperative treatment has been shown to have higher nonunion rates, thus should only be selected for a specific patient population with minimally displaced fractures or those that are unfit for surgery. Surgical management is recommended with prosthetic loosening, fracture nonunion, or failure of nonoperative treatment. Surgical options include open reduction and internal fixation, revision arthroplasty, or hybrid fixation. Careful evaluation, decision making, and planning is required in the treatment of these fractures.

Reliability of Current Classification Systems for Periprosthetic Fractures of the Humerus

OBJECTIVE

Numerous classification systems exist to evaluate periprosthetic humerus fractures, although most are based on limited patient numbers. The Wright and Cofield system is the most widely used classification system. We sought to evaluate the interobserver and intraobserver reliabilities of this system compared with the Unified Classification System (UCS) using the largest patient sample to date.

METHODS

This retrospective study identified patients between December 2011 and January 2021 with a periprosthetic fracture of the humerus around the stem of a shoulder arthroplasty component. Three upper extremity fellowship-trained surgeons evaluated all radiographs for stem stability, evidence of preinjury stem loosening, Wright and Cofield classification, UCS classification, and recommended treatment for each case at 2 timepoints separated by 2 months. The kappa statistic for interobserver and intraobserver reliability was calculated.

RESULTS

Seventy-six patients were included. There was moderate interobserver (kappa 0.53) and substantial intraobserver (kappa 0.69) agreement when classifying stem stability after fracture. There was moderate interobserver (kappa 0.48) and intraobserver (kappa 0.60) agreement when evaluating for stem loosening before fracture. There was fair interobserver (kappa 0.29) and moderate intraobserver (kappa 0.51) agreement regarding the UCS class. There was moderate interobserver (kappa 0.41) and intraobserver (kappa 0.57) agreement regarding the proposed treatment. There was slight interobserver (kappa 0.04) and moderate intraobserver (kappa 0.44) agreement regarding the Wright and Cofield classification.

CONCLUSION

The Wright and Cofield system is less reliable than the UCS classification. A more reliable and clinically relevant classification system is needed to standardize discussion of periprosthetic proximal humerus fractures.

[Revision surgery in reverse shoulder arthroplasty : Management of the most common complications]

BACKGROUND

In recent years, the number of reverse shoulder arthroplasty implantations has increased continuously and a higher number of revision surgeries due to complications can be expected in the future. Current data show a mean complication rate for RSA of around 4%. The most common complications are instability, infection, component loosening, and periprosthetic fracture.

TREATMENT OPTIONS

Revision surgery for RSA is challenging, and an individual treatment plan is necessary. For prosthetic instability, different operative or non-operative treatment options are available. Revision surgery for periprosthetic infection with replacement of the prosthesis is usually necessary for infection management. The treatment of periprosthetic fractures is based on techniques of general fracture treatment and depends on the fracture type. Knowledge of complications and risk factors may decrease complication rates in primary reverse shoulder arthroplasty in the future.

Spatial Anatomy of the Radial Nerve in the Extended Deltopectoral Approach

The goal of this study was to define safe zones to prevent radial nerve injury in an extended deltopectoral approach. Relative distances of the upper margin (UMRN) and lower margin (LMRN) of the radial nerve to the proximal and distal borders of the pectoralis major and deltoid insertions were measured in 20 cadaveric arms. Four proximal humeral zones were identified (zone I, proximal border of the pectoralis major tendon to the proximal border of the deltoid tendon; zone II, proximal border of the deltoid tendon to the distal border of the pectoralis major tendon; zone III, distal border of the pectoralis major tendon to the distal border of the deltoid tendon; and zone IV, distal to the distal border of the deltoid tendon). On fluoroscopic measurement, mean distances between the UMRN and the proximal border of the pectoralis major tendon and the proximal border of the deltoid tendon were 71.6±2.1 mm and 26.2±2.5 mm, respectively. The incidence of the radial nerve in the spiral groove within each defined zone was as follows: zone I, 0%; zone II, 50%; zones III and IV, 100%. There was a significant association between anatomic zone and radial nerve entry into the spiral groove, χ²(3, N=88)=64.53, P<.001. The proximal border of the pectoralis major tendon to the proximal border of the deltoid tendon (zone I) is a safe location to avoid injury to the radial nerve. We recommend placing cerclage wires proximal to zone I from lateral to medial to avoid entrapment of the radial nerve. [Orthopedics. 2023;46(1):e31-e37.].

Inadvertent, intraoperative, non- to minimally displaced periprosthetic humeral shaft fractures in RTSA do not affect the clinical and radiographic short-term outcome

INTRODUCTION

Little information is available on the clinical and radiographic outcome of intraoperative, non- to minimally displaced humeral fractures that occur during implantation of a stemmed, reverse shoulder prosthesis but are only recognized on routine postoperative radiographs. The goal of this study is to report the clinical and radiographic outcome for this rarely reported fracture type.

MATERIALS AND METHODS

39 conservatively treated non- to minimally displaced intraoperative periprosthetic humeral fractures after stemmed RTSA were detected from our radiographic database between 1.1.2006 and 31.1.2018. Exclusion criteria were lack of patient consent, preoperative humeral fracture, and revision arthroplasties. Clinical (absolute and relative Constant score, the Subjective Shoulder Value) and radiographic (conventional radiographs) assessment was performed preoperatively, at 6 weeks (only radiographically) and at latest follow-up with a minimum follow-up of 2 years.

RESULTS

35 patient's with a mean age of 72 years (range 32-88, SD ± 11 years) and a mean follow-up of 53 months (range 24-124, SD ± 31) were included in the study. At latest follow-up, all clinical outcome parameters except external rotation improved significantly. A complication rate of 17% (n:6) was recorded. At 6 weeks after the index surgery, none of the radiographs showed a fracture displacement or a sintering of the stem. At latest follow-up, all fractures were healed and no stem loosening was observed in any of the shoulders.

CONCLUSIONS

Non- to minimally displaced intraoperative periprosthetic humeral fractures in RTSA have an incidence of about 5% in this series of mainly uncemented press-fit stems. They generally heal without any further treatment and are not associated with stem loosening or compromise the clinical outcome after primary RTSA. Except slight restriction in the postoperative rehabilitation protocol, no further attention or action is needed.

Surgical outcomes of periprosthetic distal femur fractures after total knee arthroplasty classified by Su et al. system

Background

Periprosthetic fractures of the distal femur remain a challenge to treat due to variations in both patient- and fracture-specific factors. This study was designed to analyze the outcomes of different subtypes of periprosthetic distal femur fractures based on the Su et al. classification system.

Methods

Thirty-six patients were classified with Su et al. system. All Type I and II fractures were managed with a locking plate. Most Type III fractures were managed with locking plate, while two were managed with long-stem revision arthroplasty due to evidence of implant loosening. Outcomes were measured and analyzed based on healing time, revision rate, and complication rate.

Results

Of the 36 patients, 30 (83.3%) achieved acceptable fracture union, while the remaining 6 (16.7%) experienced either delayed union or non-union. Type I fractures showed a significantly lower healing time than Type II and III fractures managed by locking plate. Delayed union was present in the Type II group, while non-union was recorded for two Type III fractures. Need for revision was more prevalent in fracture Types II and III.

Conclusion

The Su et al. system of classification for periprosthetic fractures of the distal femur matches the clinical outcomes of this study and would seem to be useful in the approach to the treatment of these fractures. The majority of these fractures can be managed with locking plate with reasonable results. However, if the implant is loosened in Type III fractures, revision arthroplasty is suggested.

Periprosthetic humerus fractures after shoulder arthroplasty: an evaluation of available classification systems

BACKGROUND

Periprosthetic proximal humerus fractures (PPHFs) are a detrimental complication of shoulder arthroplasty, yet their characterization and management have been poorly studied. We aimed to determine the intra- and interobserver reliability of 4 previously described PPHF classification systems to evaluate which classifications are the most consistent.

METHODS

We retrospectively reviewed 32 patients (34 fractures) that were diagnosed with a PPHF between 1990 and 2017. Patient electronic medical records and research electronic data capture (REDCap) were used for data collection. Post-PPHF radiographs in multiple views for all 34 cases were organized into an encrypted, randomized Qualtrics survey. Four blinded fellowship-trained shoulder and elbow surgeons graded each fracture using previously reported classification systems by (1) Wright and Cofield (1995), (2) Campbell et al (1998), (3) Worland et al (1999), and (4) Groh et al (2008), along with selecting a preferred management strategy for each fracture. Grading was performed twice with at least 2 weeks between each randomized attempt. Intraobserver reliability was calculated as an unweighted Cohen kappa coefficient between attempt 1 and attempt 2 for each surgeon. Interobserver reliability and agreeability between surgeons' preferred management strategies were calculated for each classification system using Fleiss kappa coefficient. The kappa coefficients were interpreted using the Landis and Koch criteria.

RESULTS

The average intraobserver kappa coefficient for each classification was as follows: Wright and Cofield = 0.703, Campbell = 0.527, Worland = 0.637, Groh = 0.699. The overall Fleiss kappa coefficient for interobserver reliability for each classification was as follows: Wright and Cofield = 0.583, Campbell = 0.488, Worland = 0.496, Groh = 0.483. Interobserver reliability was significantly greater with the Wright and Cofield classification. Using Landis and Koch criteria, all the classification systems assessed demonstrated only moderate interobserver agreement. Additionally, the mean interobserver agreeability kappa coefficient for preferred management strategy was 0.490, indicating only moderate interobserver agreement.

CONCLUSION

There is only moderate interobserver reliability among the 4 PPHF classification systems and the preferred management strategy for the fractures assessed. Of the 4 PPHF classification systems, Wright and Cofield demonstrated the greatest mean intraobserver reliability and overall interobserver reliability. Our study highlights a need for the development of a PPHF classification system that can achieve high intra- and interobserver reliability and that can allow for a standardized treatment algorithm in the management of PPHFs.

Periprosthetic Postoperative Humeral Fractures After Shoulder Arthroplasty

The increased utilization of shoulder arthroplasty, including revision procedures, combined with rises in life expectancy, is expected to translate into a substantial increase in periprosthetic humeral fractures. The evaluation and management of these fractures needs to be updated to consider fractures that complicate anatomic and reverse arthroplasties and contemporary short-stem and stemless implants. Although conservative treatment is successful in a large proportion of these fractures, several surgical reconstructive techniques are required for the management of all fracture types. Surgical options include internal fixation, graft augmentation, standard revision procedures, and occasionally complex reconstructions including modular segmental prosthesis and allograft prosthetic composites. Most studies on the outcomes of periprosthetic humeral fractures have analyzed small samples and have typically reported on anatomic total shoulders with a standard-length humeral implant. Additional research is required to optimize the management of periprosthetic postoperative humeral fractures in the era of reverse arthroplasty, short stems, and stemless arthroplasty.

Is the Posterior Approach With Posterior locking compression plate and Anterior Allograft Useful and Safe in the Treatment of Periprosthetic Humeral Fractures Following Reverse Total Shoulder Arthroplasty?

Introduction

As the reverse total shoulder arthroplasty (RTSA) surgery has dramatically increased in the last few decades, many complications have followed through. The periprosthetic fracture, at the moment, is still a subject of debate in the orthopedic world. In this monocentric study, along with a literature review of periprosthetic humeral fractures, we would present our institutional experience with the treatment of periprosthetic humeral fractures with a posterior humeral approach, posterior cortex plate fixation, anterior strut allograft, screws, and cerclage wires.

Materials and Methods

Our study consisted in a prospective monocentric study based on 18 patients, with a mean age of 75.3 years (range 64–88), all following a reverse shoulder total arthroplasty (RTSA). Postoperative follow-ups were taken at 1, 6, and 12 months with objective measurement of shoulder motion and strength, while clinical outcome measures were assessed using the American Shoulder and Elbow Surgeons (ASES score) and visual analog scale (VAS) for pain. Together with that, we performed a literature review focused on the management of periprosthetic humeral fractures after shoulder arthroplasty.

Results

All fractures consolidated without complication at a mean 4.2 months (range 3–6). At final follow-up, the average active shoulder flexion was 88° (range 62–129°), active abduction 73° (range 52–91°) and active external rotation 22° (range 3–56°). The average ASES score was 73 (range 59–97), while average VAS score was 1.1 (range 0–3).

Discussion

Surgical treatment of periprosthetic humeral fractures following a shoulder arthroplasty remains a hard challenge for every surgeon, and their treatment must consider fracture’s location, displacement, and local bone quality.

Conclusions

The posterior approach with a posterior plate placement and anterior strut allograft, which is appliable only in case of a B or C type fracture according to Worland classification, could be a good treatment option for periprosthetic humeral fractures.

Management of periprosthetic fractures of the humerus : a systematic review

AIMS

The aim of this study was to investigate the outcome of periprosthetic fractures of the humerus and to assess the uniformity of the classifications used for these fractures (including those around elbow and/or shoulder arthroplasties) by performing a systematic review of the literature.

METHODS

A systematic search was conducted using the National Institute for Health and Care Excellence Healthcare Databases Advance Search. For inclusion, studies had to report clinical outcomes following the management of periprosthetic fractures of the humerus. The protocol was registered on the PROSPERO database.

RESULTS

Overall, 40 studies were included, involving a total of 210 patients. The fractures were reported using very heterogeneous classification systems, as were the functional outcome scores. A total of 60 patients had nonoperative treatment with a 50% rate of nonunion. Fixation was undertaken in 99 patients; successful union was obtained in 93 (93%). Revision of either the humeral stem or the whole arthroplasty was reported in 79 patients with a high rate of union (n = 66; 84%), and a mean rate of complications of 29% (0% to 41%).

CONCLUSION

This study highlighted a lack of uniformity in classifying these fractures and reporting the outcome of their treatment. The results may help to inform decision-making with patients, particularly about the rate of complications of nonoperative treatment. There is a need to improve the reporting of the pattern of these fractures using a uniform classification system, and the harmonization of the collection of data relating to the outcome of treatment. Based on this review, we propose a minimum dataset to be used in future studies. Cite this article: Bone Joint J 2022;104-B(4):416-423.

A Long-Term Follow-Up of Post-Operative Periprosthetic Humeral Fracture in Shoulder Arthroplasty

Background

During the last decades, the growing number of shoulder replacement has increased the associated complications. Periprosthetic fractures have a low incidence but can be a severe clinical condition, especially in elderly population. There are still no guidelines to define the best treatment protocol for post-operative periprosthetic humeral fractures. Factors associated to these fractures and consequently the decision-making for the best treatment seem to be patient-related but also correlated with the type of implant. The aim of this study is to analyze the patient’s risk factors, fracture pattern, implant type and treatment, evaluating the outcome with a long-term follow-up.

Methods

A retrospective study was performed on more than 2700 shoulder prostheses implanted over 10 years in two specialized centers, identifying 19 patients who underwent surgery for post-operative periprosthetic fracture. Gender, age, comorbidities, type of prosthetic implant, type of fracture, and cortical index of each patient were evaluated. All patients underwent surgery and were evaluated with a mean follow-up of 5 years with radiographic controls and functional assessment with the Constant–Murley score.

Results

Complete healing was achieved in 18 of 19 patients. All patients presented a lower Constant–Murley score than the pre-fracture score, there were no significant differences between prosthetic implants, and the cortical index was lower than the threshold level in more than 60% of cases.

Conclusion

The results of this study showed that a correct preoperative planning is essential to evaluate the type of implant and possible signs of stem mobilization. With a stable stem, it is preferable to maintain it and proceed to a synthesis. The decision process is more complex in periprosthetic fractures with a reduced cortical index, when some radiolucency lines are present in stems with high primary stability, because it is not always indicative of an unstable stem.

Level of Evidence

Therapeutic III

Primary stability of fixation methods for periprosthetic fractures of the humerus: a biomechanical investigation

BACKGROUND

The incidence of periprosthetic fractures of the proximal humerus is gradually increasing, following an increase in reverse shoulder arthroplasties in recent years. Locking plate fixation and revision arthroplasty are both valuable treatment methods. However, the primary stability of fixation methods for periprosthetic fractures has not been investigated in detail. The aim of this study was to analyze and compare the primary stability of the common treatment measures.

MATERIALS AND METHODS

Cemented reverse total shoulder arthroplasty (Delta Xtend; DePuy Synthes, Warsaw, IN, USA) was performed in 5 shoulders, and a distal, mid-diaphysis humeral fracture (Wright and Cofield type B) was induced. The implant was left in place, and 3 distinct fixation scenarios were tested: osteosynthesis using 4.5-mm locking plate fixation (subgroup A), 4.5-mm locking plate fixation with an additional 3.5-mm locking plate (subgroup B), and 4.5-mm locking plate fixation with an additional K-wire cerclage (subgroup C). The specimens were tested in a biomechanical setup simulating activities of daily living including rotation. Strain gauges (4-wire strain at 120 Ω; Vishay Measurements Group, Chartres, France) mounted on the 4.5-mm locking plates were used to evaluate the strain of the fixation and to give an estimate of primary stability.

RESULTS

Regarding the simulation of activities of daily living, no statistically significant differences were found in the measured strains on the locking plate between subgroups A, B, and C. A maximum measured strain of 216.85 μm/m in subgroup A resulted in bending of the locking plate (length, 134 mm) of 0.03 mm. In subgroup B (277.01 μm/m), the plate strained 0.04 mm compared with a strain measurement of 0.01 mm in subgroup C (75.93 μm/m).

CONCLUSION

Additional K-wire cerclages or additional 3.5-mm locked plating did not increase primary stability. With a stable prosthetic implant in place, 4.5-mm locked plating is sufficient to address periprosthetic humeral shaft fractures in the present in vitro setup.

Problems, complications, and reinterventions in 4893 onlay humeral lateralized reverse shoulder arthroplasties: a systematic review (part I-complications)

Background

Several modifications to the original Grammont reverse shoulder arthroplasty (RSA) design have been proposed to prevent distinctive issues, such as both glenoid and humeral lateralization. The aim of this systematic review was to determine rates of problems, complications, reoperations, and revisions after onlay lateralized humeral stem RSA, hypothesizing that these are design related.

Methods

This systematic review was performed in accordance with the PRISMA statement guidelines. A literature search was conducted (01.01.2000–14.04.2020) using PubMed, Cochrane Reviews, Scopus, and Google Scholar employing several combinations of keywords: “reverse shoulder arthroplasty,” “reverse shoulder prosthesis,” “inverse shoulder arthroplasty,” “inverse shoulder prosthesis,” “problems,” “complications,” “results,” “outcomes,” “reoperation,” “revision.”

Results

Thirty-one studies with 4893 RSA met inclusion criteria. The 892 postoperative problems and 296 postoperative complications represented overall problem and complication rates of 22.7% and 7.5%, respectively. Forty-one reoperations and 63 revisions resulted, with an overall reoperation rate of 1.7% and overall revision rate of 2.6%.

Conclusions

Problem, complication, and reintervention rates proved acceptable when implanting a high humeral lateralization stem in RSA. The most frequent problem was scapular notching (12.6%), and the most common postoperative complication was scapular stress fracture (1.8%). An overall humeral complication rate of 1.9% was identified, whereas short stems reported no humeral fractures or stem loosening. Infections (1.3%) proved to be the most common reason for component revision, and instability had a complication rate of 0.8%.

Level of evidence

Systematic review IV

Nonoperative Treatment of Periprosthetic Humeral Shaft Fractures After Reverse Total Shoulder Arthroplasty

Few studies report on periprosthetic humeral shaft fractures after reverse total shoulder arthroplasty (RTSA). The authors evaluated outcomes of 5 patients with this complication who were initially treated nonoperatively. Of 152 patients who underwent RTSA at the authors' institution from 2012 to 2017, 4 experienced periprosthetic humeral shaft fractures. One patient was referred to the authors for fracture treatment. All 5 patients were initially treated nonoperatively. The mean duration of follow-up was 11.5 months (range, 1.5-26 months). The authors analyzed time to fracture union, Single Assessment Numeric Evaluation (SANE) score, visual analog scale (VAS) score for pain, and active shoulder range of motion. Fracture union occurred in 4 patients treated nonoperatively at a mean of 4.4 months. Mean SANE score was 55 of 100 (range, 20-85). Mean VAS score was 3.4 of 10 (range, 0-8). Mean forward elevation was 83° (range, 45°-110°); mean abduction was 65° (range, 45°-80°); and mean external rotation with the arm at the side was 15° (range, 0°-30°). Many factors must be considered when customizing treatment for patients with periprosthetic fracture after RTSA. This case series indicates that nonoperative treatment of postoperative periprosthetic humeral shaft fractures can be successful. [Orthopedics. 2020;43(6):e553-e560.].

[Periprosthetic fractures of the shoulder girdle]

Periprosthetic fractures of the shoulder girdle will increasingly become part of routine clinical practice due to rising numbers of joint replacements and the demographic changes. Diagnostically, the status of the rotator cuff, bed of the implant (stable or loose), type of shoulder arthroplasty as well as exclusion of joint infections are crucial for therapeutic decision-making. Novel imaging tools, such as dual-energy computed tomography provide improved preoperative planning options. The unified classification system describes the fracture location, stability of the prosthesis and quality of the bone. While nonoperative treatment is reserved for patients with severe pre-existing conditions and nondisplaced fractures, the standard treatment of fractures with a stable bed include fixation with cerclage wiring and angular stable plates. Modern implant systems with variable angle screw holes, attachment plates and hinges enable secure fixation around the stem. In cases of a loose stem revision arthroplasty is necessary. There are currently only a limited number of clinical studies with only few patients that analyzed clinical and radiological results. Thus, increased research efforts are indispensable in order to compare treatment options and improve treatment quality.

[Periprosthetic fractures: basics, classification and treatment principles]

Periprosthetic fractures (PPFx) are becoming an increasingly important topic in orthopedics and trauma surgery due to the rising number of endoprosthetic joint replacements. The recently published unified classification system (UCS) has replaced numerous historical classification systems and can be applied to all PPFx regardless of the bone or joint involved. The treatment of PPFx requires individual therapeutic concepts taking patient-dependent and patient-independent factors into consideration. The conservative treatment of PPFx is only justified in exceptional situations. In contrast, the choice between operative treatment and deciding between osteosynthesis or revision arthroplasty is particularly based on the assessment of the implant stability. In order to achieve fracture consolidation and also a good functional outcome, knowledge of the basic biomechanical principles of operative (osteosynthesis or endoprosthesis) treatment of periprosthetic fractures is necessary.

Periprosthetic Fractures in Reverse Total Shoulder Arthroplasty: Current Concepts and Advances in Management

PURPOSE OF REVIEW

Expanded indications for reverse total shoulder arthroplasty (RSA) have raised awareness of associated complications, including periprosthetic fractures. The purpose of this article was to provide a comprehensive update on how, when, and why RSA-related periprosthetic fractures occur, as well as to describe the current treatment strategies.

RECENT FINDINGS

Periprosthetic acromial and scapular spine fractures occur in up to 4.3% of cases and periprosthetic humeral fractures occur in approximately 3.5% of RSA procedures. Fractures of the coracoid process and clavicle have also been reported. Current literature has identified several risk factors for intraoperative or postoperative fracture, including underlying osteoporosis, revision arthroplasty, use of a superiorly placed screw during metaglene fixation, and disruption of the scapular ring by transection of the coracoacromial ligament. Periprosthetic fracture associated with RSA is a clinically significant event that warrants prolonged postoperative vigilance, timely diagnosis, and shared patient decision-making regarding treatment. Further research is needed to identify optimal treatment strategies and characterize long-term clinical outcomes following RSA-related periprosthetic fracture.

Revision of a Complex Periprosthetic Humerus Fracture with Two-Thirds of Humerus Bone Loss with an Allograft-Prosthetic Composite Reverse Shoulder Arthroplasty

Shoulder arthroplasty is becoming an increasingly standard procedure in the United States. In conjunction with an aging population and increased prevalence of osteoporosis, proper management of periprosthetic humerus fractures is of great interest to orthopedic surgeons. Several periprosthetic humeral fracture classification systems take into consideration the fracture location and implant stability, but they do not address the type of bone defects or amount of bone available for revision surgery. The lack of description and guidance in the different varieties of humerus bone defects limits current classification system utility in cases with severe bone loss. There are previous case reports of revisions of periprosthetic humerus fractures with an allograft-prosthetic composite reverse total shoulder replacement. Different from previously reported cases, the case described in this article presented the treatment of a complex humerus fracture with loss of more than two-thirds of the patient’s native humerus. Due to the extensive humerus bone loss, we modified the surgical techniques previously published to allow for a successful surgery.

Surgical treatment of periprosthetic humerus fractures and algorithm

INTRODUCTION

Periprosthetic humerus fractures are infrequent and sometimes difficult to treat. There is limited literature and no consensus on the handling of these fractures. The objective of this study was to compare our results with those published in the literature, in order to improve our care and propose a management algorithm.

MATERIAL AND METHOD

Observational study of 10cases of periprosthetic humerus fractures with a mean follow-up of the patients of 23months. An analysis of sociodemographic, radiological and surgical variables was performed. They were reviewed clinically and by telephone using the UCLA Shoulder Score and Quick-DASH scales. A systematic search was made in Pubmed for periprosthetic humerus fractures, for a literature review with which to compare our series.

RESULTS

We analysed 10patients with an average age of 69.4years (37-91). Of the patients, 90% underwent surgery through open reduction and internal fixation. Nine of the ten patients consolidated in a mean time of 6.2months (range 5-12), the remaining suffered a new fracture 5months after the intervention, who were reoperated and a new osteosynthesis performed with bone allograft. In the UCLA scale there was a decrease of 10.66points, and an increase of 27.3points in the Quick-DASH, at the end of the follow-up.

CONCLUSIONS

In our series of cases we found similarities in the literature, in relation to demographic aspects and obtaining good radiographic results, which do not correspond to the functional outcome of patients.

Late-Onset Radial Nerve Palsy After Closed Treatment of a Periprosthetic Humerus Fracture: A Case Report

CASE

A 58-year-old woman underwent successful reverse total shoulder arthroplasty for a proximal humerus fracture. Three years later, she sustained a periprosthetic humerus fracture after a fall and was treated conservatively. She healed with an abundance of callus and subsequently developed delayed-onset radial nerve palsy at 3 months, despite minimal change in humeral alignment and avoidance of the use of any compressive external braces or splints.

CONCLUSIONS

Minimally displaced periprosethetic humerus fractures can lead to delayed radial nerve palsy from callus entrapment, and there should be increased awareness of this potential complication when counseling and treating patients conservatively.

Post-operative periprosthetic humeral fractures after reverse shoulder arthroplasty: a review of the literature

Background and aim of the work: Post-operative periprosthetic shoulder fractures incidence is gradually raising due to aging of population and increasing of reverse total shoulder arthroplasty (RTSA). Management of this complication represents a challenge for the orthopedic surgeon. Aim of the present study is to critically review the recent literature about epidemiology, risk factors, diagnosis, management and outcome of post-operative periprosthetic humeral fractures occurring on RTSA. Methods: A systematic search of Embase, Medline and Pubmed was performed by two reviewers who selected the eligible papers favoring studies published in the last ten years. Epidemiology, risk factors, diagnostic features, clinical management and outcome of different techniques were all reviewed. Results: 31 studies including reviews, meta-analysis, case reports, clinical and biomechanical studies were selected. Conclusions: Correct clinical management requires adequate diagnosis and evaluation of risk factors. Conservative treatment is rarely indicated. Locking plate fixation and revision arthroplasty are both valuable treatment methods. Surgical technique should be chosen considering age and functional demand, comorbidities, fracture morphology and location, bone quality and stability of the implant. Given the correct indication all surgical treatment can lead to satisfactory clinical and radiographic results despite a relevant complication rate. (www.actabiomedica.it)

The router bit extraction technique for removing a well-fixed humeral stem in revision shoulder arthroplasty

Aims

A number of methods have been described to remove a well-fixed humeral implant as part of revision shoulder arthroplasty. These include the use of cortical windows and humeral osteotomies. The router bit extraction technique uses a high-speed router bit to disrupt the bone-implant interface. The implant is then struck in a retrograde fashion with a square-tip impactor and mallet. The purpose of this study was to determine the characteristics and frequency of the different techniques needed for the removal of a well-fixed humeral stem in revision shoulder arthroplasty.

Patients and Methods

Between 2010 and 2018, 288 revision shoulder arthroplasty procedures requiring removal of a well-fixed humeral component were carried out at a tertiary referral centre by a single surgeon. The patient demographics, indications for surgery, and method of extraction were collected.

Results

Of the 288 revisions, 284 humeral stems (98.6%) were removed using the router bit extraction technique alone. Four humeral stems (1.39%) required an additional cortical window. Humeral osteotomy was not necessary in any procedure. Most of the humeral stems removed (78.8%) were cementless. Of the four humeral stems that required a cortical window, three involved removal of a hemiarthroplasty. Two were cemented and two were cementless.

Conclusion

The router bit extraction technique removed a well-fixed humeral component in a very high proportion of patients (98.6%). This method allows surgeons to avoid more invasive approaches involving a cortical window or humeral osteotomy, and their associated complications. Cite this article: Bone Joint J 2019;101-B:1280–1284

Safe Zones for Cerclage Wiring of the Humeral Diaphysis

Cerclage wiring of the humeral diaphysis entails particular danger to the radial nerve and the deep brachial artery. We sought to delineate safe zones for minimally invasive cerclage wiring of the humeral diaphysis, specifically in relation to the radial nerve and accompanying vasculature. Cerclage wires were percutaneously inserted into three groups of fresh-frozen cadaveric humeri. Group 1-proximal midshaft humerus at 30% of humeral height (n = 4); Group 2-midshaft spiral groove at 45% of humeral height (n = 4); and Group 3-distal midshaft humerus at 60% of humeral height (n = 4). Subsequently, an extensive surgical exploration of the arteries and nerves around the humerus was performed, noting any disturbance to the vessels or nerves and measuring the distance from the cerclage wire to the radial nerve. Neurovascular structures were injured in 75% of specimens when the cerclage wire was inserted at the level of the spiral groove. Both posterior structures, e.g. the radial nerve and the deep brachial artery, and medial structures, e.g., the median nerve and brachial artery, were incarcerated. Application of the cerclage at 30% or 60% of humeral height did not cause neurovascular injury. Minimally invasive application of the cerclage wire at the spiral groove, which is at 45% of humeral height, is likely to cause injury to neurovascular structures. Application of the cerclage at the proximal or distal midshaft humeral areas is associated with less risk of such injury. Clin. Anat. 33:552-557, 2020. © 2019 Wiley Periodicals, Inc.

[Conservative treatment of periprosthetic humeral fractures years after cemented fracture prostheses : A case series]

BACKGROUND

The exact incidence of postoperative periprosthetic humeral fractures (PPHF) months or years after fracture-related implantation of a hemiprosthesis is unknown. The currently available literature is predominantly concerned with operative treatment approaches. As a rule, these involved older patients and severe fracture conditions so that severe complications and unsatisfactory healing results were described. This article presents an alternative conservative treatment approach which is discussed based on the results of treatment.

PATIENTS AND METHODS

Between 2011 and 2016 a conservative treatment of 5 female patients with PPHF could be carried out. Of the patients 4 were clinically and radiologically controlled at a mean follow-up time of 23 months. The fifth patient died 2 months after the trauma and only partial information of the treatment was available.

RESULT

There were no intrahospital complications and just one posthospital complication. In the case of the patient who later died, repeated and unauthorized removal of the upper arm brace occurred in the nursing institution resulting in a lesion of the radial nerve. Of the four patients who completed treatment, three were very satisfied with the outcome of treatment. The mean DASH (Disabilities of Arm, Shoulder and Hand) and Oxford shoulder scores were on average 74 and 25 points, respectively. At the time of the follow-up examination all patients were free of pain, without the use of analgesics; however, there were still some limitations in the activities of daily life, which in three of the four patients was similar to the results following implantation of the fracture prosthesis.

CONCLUSION

The conservative treatment of PPHF can be a safe treatment option in multimorbid and chronically ill patients. A close outpatient control and good patient compliance are important. In incompliant and dementia patients, the risk of failure of conservative treatment is increased.

Sidus Stem-Free Shoulder System for primary osteoarthritis: short-term results of a multicenter study

BACKGROUND

The aim of this prospective multicenter study was to evaluate clinical and radiologic results of a new metaphyseal anchored system. This system features a different anchor geometry that potentially leads to better bony integration and less loosening.

METHODS

From November 2012 until December 2015, 148 patients (151 shoulders) were treated with the Sidus Stem-Free Shoulder System at 9 centers in Europe. The main indication was primary osteoarthritis (80.1%). This analysis only includes patients diagnosed with primary osteoarthritis (n = 121). A clinical evaluation was performed using the Constant-Murley score, Subjective Shoulder Value, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, and range of motion. Radiologic assessment was based on the occurrence of radiolucent lines and signs of implant migration, osteolysis, loosening, and heterotopic ossification.

RESULTS

We evaluated 105 patients after a follow-up period of 2 years. There were 53 women and 52 men. The average age was 64 years. Total shoulder arthroplasty was performed in 73 cases and hemiarthroplasty in 32. The Constant-Murley score improved from 26 points preoperatively to 70 points at 2 years' follow-up (P < .001). The Subjective Shoulder Value increased from 34% to 84% (P < .001), and the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form increased from 34 points to 86 points (P < .001). Radiologically, neither migration nor loosening was found. However, radiolucent lines of 2 mm or greater could be detected around the glenoid in 2 cases, but none of them have had clinical relevance yet. The overall complication rate was 6.7%, and the revision rate was 0%.

CONCLUSION

Patients with the Sidus Stem-Free Shoulder System achieve good clinical and radiologic short-term results that are comparable with the results of other stem-free shoulder implants.

Long-term humeral complications after Grammont-style reverse shoulder arthroplasty

BACKGROUND

Recent experiences with Grammont reverse shoulder arthroplasty (RSA) have revealed some problems related to the biomechanical changes of the shoulder and humeral stem complications. We analyzed humeral complications in a long-term follow-up of a large series of RSAs, searching for correlations between these and the initial etiology, the follow-up duration, and the clinical outcomes.

MATERIALS AND METHODS

Preoperative and postoperative clinical and radiologic assessments of 1035 RSAs with a minimum 5-year follow-up (implanted in 7 specialized shoulder centers between 1993 and 2010) were retrospectively collected. Postoperative humeral complications, managed conservatively or surgically, were radiographically documented.

RESULTS

Overall, a 3.3% rate of postoperative humeral complications was found in our database. We identified 17 cases (1.6%) with postoperative humeral fractures, 15 cases (1.4%) with aseptic humeral loosening, and 3 cases (0.3%) with humeral stem disassembly. The humeral complications were more frequent in RSAs implanted for tumors, fracture sequelae, and revision for failed arthroplasty.

DISCUSSION

Humeral complications after RSA are not rare, increase with longer follow-up, and have a negative impact on functional outcomes. Postoperative humeral fractures are more frequent in elderly patients, operated on through a superior approach, and after cemented stem implantation. In the absence of associated humeral loosening, conservative treatment should be preferred. Proximal humeral bone loss (due to revisions and tumors) is the most significant risk factor for humeral loosening. Implant unscrewing was initially related to a technological problem, which has been solved, and this complication has disappeared.

Humeral shaft fractures

Fractures of the humeral shaft are common injuries with multiple management strategies. Many still regard nonoperative management as the standard of care; however, as the understanding of these injuries increases, treatment recommendations are also evolving. Fracture pattern, fracture location, and identifiable patient risk factors may predict poor outcome with nonoperative management, and earlier operative intervention may be recommended. Operative management includes open reduction and internal fixation through a variety of exposures, intramedullary nail fixation, and external fixation. With increasing rates of shoulder arthroplasty, periprosthetic humeral shaft fractures also deserve special consideration.

Validation of a new classification for periprosthetic shoulder fractures

INTRODUCTION

Successful treatment of periprosthetic shoulder fractures depends on the right strategy, starting with a well-structured classification of the fracture. Unfortunately, clinically relevant factors for treatment planning are missing in the pre-existing classifications. Therefore, the aim of the present study was to describe a new specific classification system for periprosthetic shoulder fractures including a structured treatment algorithm for this important fragility fracture issue.

METHODS

The classification was established, focussing on five relevant items, naming the prosthesis type, the fracture localisation, the rotator cuff status, the anatomical fracture region and the stability of the implant. After considering each single item, the individual treatment concept can be assessed in one last step. To evaluate the introduced classification, a retrospective analysis of pre- and post-operative data of patients, treated with periprosthetic shoulder fractures, was conducted by two board certified trauma surgery consultants.

RESULTS

The data of 19 patients (8 male, 11 female) with a mean age of 74 ± five years have been analysed in our study. The suggested treatment algorithm was proven to be reliable, detected by good clinical outcome in 15 of 16 (94%) cases, where the suggested treatment was maintained. Only one case resulted in poor outcome due to post-operative wound infection and had to be revised.

CONCLUSIONS

The newly developed six-step classification is easy to utilise and extends the pre-existing classification systems in terms of clinically-relevant information. This classification should serve as a simple tool for the surgeon to consider the optimal treatment for his patients.

Stemless Prosthesis for Total Shoulder Arthroplasty

The fourth generation of humeral components currently are being used in anatomic shoulder arthroplasty. Anatomic shoulder arthroplasty implants have evolved to better re-create anatomy, improve fixation, preserve bone, and facilitate revision surgery. Most of the design changes for shoulder arthroplasty implants have centered on the humeral stem, with a transition to shorter, metaphyseal humeral stems. Many of these humeral component design changes may be beneficial; however, long-term studies are necessary to determine if the results of anatomic shoulder arthroplasty with the use of newer humeral components can match those of anatomic shoulder arthroplasty with the use of older humeral components.

Surgical Fixation of Periprosthetic Humerus Fractures Using an Extension Plate: Surgical Technique and Report of 5 Cases

Periprosthetic fractures after shoulder arthroplasty occur in up to 2% of patients. In patients with stable components who fail or cannot undergo nonoperative management, stable fixation is required. We present a new technique to obtain proximal fixation around the humeral component using a 4.5-mm large fragment plate and a 3.5-mm attachment plate.

Humeral shaft cerclage wiring: a safe technique to prevent radial nerve injury

Humeral periprosthetic fractures are a challenging problem and their occurrence has increased, particularly over the last decade. The role of cerclage wires or cables in these fractures includes revisions with longer stems, and augmentation of a plate osteosynthesis in which the stem does not allow additional screw placement or structural bone grafts as supplementary fixation. These procedures are demanding because of the proximity of the radial nerve within the operating field. Placing a cerclage wire or cable around the fractured fragments offers a simple and safe procedure to avoid radial nerve injury or palsy in the treatment of complex humeral shaft fractures. This new technique is a simple and safe procedure to place a cerclage wire or cable around the humeral shaft.

[Prosthesis replacement in periprosthetic humeral fractures]

OBJECTIVE

Stabilization of the humerus with preservation or restoration of the shoulder function.

INDICATIONS

Always in the presence of a loose prosthesis. It may become necessary in conditions of poor bone stock and if osteosynthesis is not possible.

CONTRAINDICATIONS

Noncompliant patients due to alcohol or drugs. Local infections.

SURGICAL TECHNIQUE

The loose implant is removed using an extended anterior deltopectoral approach. After exploration of the fracture and extended soft tissue release, the glenoidal components are implanted with visualization and protection of the axillary nerve. A long stemmed implant is typically needed on the humeral side. It is anchored in the distal fragment over a length of about 6 cm. Soft tissue tension is crucial, especially with reverse shoulder arthroplasty.

POSTOPERATIVE MANAGEMENT

Postoperatively, the affected limb is immobilized for 6 weeks on a 15° shoulder abduction pillow with active assisted movement therapy up to the horizontal plane. This is followed by gradual pain-adapted increases of movement, muscle coordination, and strength.

RESULTS

In 17 patients with periprosthetic fractures of the humerus surgically treated in our institution, 4 underwent revision arthroplasty because of a loose prosthesis. No intra- or postoperative complications were observed. All fractures healed except one.

Short, Medium and Long Term Complications After Total Anatomical Shoulder Arthroplasty

Total shoulder arthroplasty (TSA) is an effective approach for the treatment of a variety of clinical conditions affecting the shoulder, including osteoarthritis, inflammatory arthritis and osteonecrosis, and the number of TSA implanted has grown exponentially over the past decade. This review gives an update of the major complications, mainly infections, instability and loosening, encountered after TSA, based on a corpus of recent publications and a dynamic approach: The review focuses on the causes of glenoid loosening, which account for 80% of the complication, and underlines the importance of glenoid positioning in the recovery of early shouder function and in the long term survival rate of TSA.

Periprosthetic humeral fractures after reverse shoulder arthroplasty. Case report

Periprosthetic fractures is a severe complication after joint replacement. The rapidly increase of reverse shoulder arthroplasty surgeries, periprosthetic humeral fractures, which are described as rare, may increase in the near future. We report the case of displaced humeral fracture bellow the stem of reverse shoulder prosthesis. The patient was an 85-year-old woman who had a total shoulder replacement 6 years previously. The surgical solution consisted of plate osteossynthesis and cerclage. This report describes an unprecedented case in Brazilian literature; and gives an overview of the existing literature including this injury classification.

Nine-year outcome after anatomic stemless shoulder prosthesis: clinical and radiologic results

BACKGROUND

Several stemless shoulder implants are available on the market, but only a few studies have presented results with sufficient mid- to long-term follow-up. The present study evaluated clinical and radiologic outcomes 9 years after anatomic stemless shoulder replacement.

METHODS

This is a prospective cohort study evaluating the stemless shoulder prosthesis since 2005. Anatomic stemless shoulder replacement using a single prosthesis was performed in 49 shoulders; 17 underwent total shoulder replacement, and 32 underwent hemiarthroplasty. Forty-three patients were clinically and radiologically monitored after a mean of 9 years (range, 90-127 months; follow-up rate, 88%). The indications for shoulder replacement were primary osteoarthritis in 7 shoulders, post-traumatic in 24, instability in 7, cuff tear arthropathy in 2, postinfectious arthritis in 1, and revision arthroplasty in 2.

RESULTS

The Constant-Murley Score improved significantly from 52% to 79% (P < .0001). The active range of motion also increased significantly for flexion from 101° to 118° (P = .022), for abduction from 79° to 105° (P = .02), and for external rotation from 21° to 43° (P < .0001). Radiologic evaluation revealed incomplete radiolucency in 1 patient without clinical significance or further intervention. No revision caused by loosening or countersinking of the humeral implant was observed.

CONCLUSIONS

The 9-year outcome after stemless shoulder replacement is comparable to that of third- and fourth-generation standard shoulder arthroplasty.

Periprosthetic fractures: epidemiology and current treatment

Periprosthetic fractures are becoming increasingly frequent due to aging population and growing number of total joint replacements involving joints different from hip and knee, such as shoulder and elbow. The treatment of these fractures still represents one of the major challenges for the orthopedic surgeon. Despite all efforts to understand and treat these patients, high rate of failure and mortality are still reported. In this review, the epidemiology of periprosthetic fractures, risk factors and results of surgical treatment are disclosed. Moreover, we propose a treatment algorithm based on the findings of the New Unified Classification System.

Total Humeral Endoprosthesis Replacement to Salvage Periprosthetic Fractures in Rheumatoid Arthritis

The authors report their experience in the management of a 53-year-old woman with rheumatoid arthritis who presented with bilateral asynchronous traumatic periprosthetic fractures of the humerus after bilateral elbow replacements. One side was treated with a long-stem revision and internal fixation with bone graft, while the other side was treated with a long-stem distal humeral replacement. She sustained pathological periprosthetic fractures on top of the long-stemmed implants. Total humeral endoprosthesis replacements were performed bilaterally as salvage procedures to provide a stable platform for her elbow and hand function. At manuscript submission, the patient was 24 months and 36 months postoperatively on the left and right sides, respectively. Her Oxford Shoulder Scores were 21 (left side) and 24 (right side). There is little information about the management of periprosthetic fractures of the humerus after long-stem revisions with severe bone loss. To the best of the authors' knowledge, this is the first case report describing the use of bilateral total humeral endoprosthesis replacements in the management of complex unstable periprosthetic fractures. This is a valuable treatment option for patients with poor bone quality, bone loss, and loose components. [Orthopedics. 2017; 40(2):e363-e366.].

[Periprosthetic humeral fractures: Strategies and techniques for osteosynthesis]

The prevalence of periprosthetic humeral fractures (PHF) is currently low and accounts for 0.6-2.4%. Due to an increase in the rate of primary implantations a quantitative increase of PHF is to be expected in the near future. The majority of PHF occur intraoperatively during implantation with an increased risk for cementless stems and when performing total arthroplasty. Additional risk factors are in particular female gender and the severity of comorbidities. In contrast, postoperative PHF mostly due to low-energy falls, have a prevalence between 0.6% and 0.9% and are significantly less common. The prognosis and functional outcome following revision by open reduction internal fixation (ORIF) essentially depend on a thorough assessment of the indications for revision surgery, the operative treatment and the pretraumatic functional condition of the affected shoulder. In the armamentarium of periprosthetic ORIF of the humerus cerclage systems and locking implants as well as a combination of both play a central role. In comminuted fractures with extensive defect zones, severely thinned cortex or extensive osteolysis a biological augmentation of the ORIF should be considered. In this context when the indications are correctly interpreted, especially in the case of a stable anchored stem, various groups have reported that a high bony union rate can be achieved. As the treatment of PHF is complex it should be performed in dedicated centers in order to adequately address potential comorbidities, especially in the elderly population.

Treatment of Periprosthetic Humerus Fractures With Open Reduction and Internal Fixation

Periprosthetic humerus fractures are relatively uncommon occurrence that can be difficult to manage nonoperatively. Locking plate technology has enhanced the surgical management of these fractures. However, adequate fixation around the stem remains of some concern. We describe an osteosynthesis technique using a locking plate utilizing eccentrically placed screw holes to place "skive screws" in the proximal end of the plate to achieve fixation around the stem of the implant. A clinical series of 5 consecutive patients treated with this technique is presented with an average follow-up of 29 months (range, 12-48). Two additional patients had less than 1-year follow-up. All patients demonstrated fracture healing. Functional outcomes were limited with only 1 patient achieving forward elevation above 90 degree, and the average American Shoulder and Elbow Surgeons Function score was 28. Pain relief was nearly uniform with an average visual analog scale pain score of 0.5.

Clinical and Radiographic Outcomes of the Simpliciti Canal-Sparing Shoulder Arthroplasty System: A Prospective Two-Year Multicenter Study

BACKGROUND

Stemmed humeral components have been used since the 1950s; canal-sparing (also known as stemless) humeral components became commercially available in Europe in 2004. The Simpliciti total shoulder system (Wright Medical, formerly Tornier) is a press-fit, porous-coated, canal-sparing humeral implant that relies on metaphyseal fixation only. This prospective, single-arm, multicenter study was performed to evaluate the two-year clinical and radiographic results of the Simpliciti prosthesis in the U.S.

METHODS

One hundred and fifty-seven patients with glenohumeral arthritis were enrolled at fourteen U.S. sites between July 2011 and November 2012 in a U.S. Food and Drug Administration (FDA) Investigational Device Exemption (IDE)-approved protocol. Their range of motion, strength, pain level, Constant score, Simple Shoulder Test (SST) score, and American Shoulder and Elbow Surgeons (ASES) score were compared between the preoperative and two-year postoperative evaluations. Statistical analyses were performed with the Student t test with 95% confidence intervals. Radiographic evaluation was performed at two weeks and one and two years postoperatively.

RESULTS

One hundred and forty-nine of the 157 patients were followed for a minimum of two years. The mean age and sex-adjusted Constant, SST, and ASES scores improved from 56% preoperatively to 104% at two years (p < 0.0001), from 4 points preoperatively to 11 points at two years (p < 0.0001), and from 38 points preoperatively to 92 points at two years (p < 0.0001), respectively. The mean forward elevation improved from 103° ± 27° to 147° ± 24° (p < 0.0001) and the mean external rotation, from 31° ± 20° to 56° ± 15° (p < 0.0001). The mean strength in elevation, as recorded with a dynamometer, improved from 12.5 to 15.7 lb (5.7 to 7.1 kg) (p < 0.0001), and the mean pain level, as measured with a visual analog scale, decreased from 5.9 to 0.5 (p < 0.0001). There were three postoperative complications that resulted in revision surgery: infection, glenoid component loosening, and failure of a subscapularis repair. There was no evidence of migration, subsidence, osteolysis, or loosening of the humeral components or surviving glenoid components.

CONCLUSIONS

The study demonstrated good results at a minimum of two years following use of the Simpliciti canal-sparing humeral component. Clinical results including the range of motion and the Constant, SST, and ASES scores improved significantly, and radiographic analysis showed no signs of loosening, osteolysis, or subsidence of the humeral components or surviving glenoid components.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.