[Crossed screw osteosynthesis of proximal humerus fractures]

Finite element analysis of different locking plate fixation methods for the treatment of ulnar head fracture

Background

Ulnar head fractures are increasingly higher with the growing proportion of the elderly people. Failure to achieve a stable anatomic reduction of ulna head fracture may lead to a distal radioulnar joint (DRUJ) dysfunction and nonunion of the distal radius. Due to the lack of the postoperative reporting outcomes and the biomechanical studies, it has not been well established about the optimal management of the comminuted distal ulna head fracture. Hence, the purpose of this study is to use finite element analysis to explain the advantages and disadvantages of ulnar-side locking plate fixation compared with dorsal-side locking plate fixation and its screw arrangement in the treatment of ulnar head fractures.

Methods

FE models of the ulnar head fracture and the models of ulnar-side locking plate and dorsal-side plate with two or three distal screws was constructed. In order to simulate forces acting on the ulnar and the osteosynthesis material during daily-life activity in subjects who underwent reconstructive surgery, we applied three loading conditions to each model, viz. 20 N axial compression, 50 N axial compression, 1 N∙m torsion moment, 1 N∙m lateral bending moments, and 1 N∙m extension bending moments. Under these conditions, values of the von Mises stress (VMS) distribution of the implant, peak VMS, the relative displacement of the head and shaft fragments between the fracture ends and the displacement and its direction of the models were investigated.

Results

The stress values of ulnar-side plates were lower than those of dorsal-side plates. And the ulnar-plate fixation system also has smaller maximum displacement and relative displacement. When adding a screw in the middle hole of the ulnar head, the values of model displacement and the peak stress in fixation system are lower, but it may evidently concentrate the stress on the middle screw.

Conclusions

In conclusion, our study indicated that ulnar-side locking plates resulted in a lower stress distribution in the plate and better stability than dorsal-side locking plates for ulnar head fracture fixation. Adding an additional screw to the ulnar head could increase the stability of the fixation system and provide an anti-torsion function. This study requires clinical confirmation of its practicality in the treatment of ulnar head fractures. This study requires clinical confirmation as to its practicality in the treatment of ulnar head fracture.

Strength recovery after proximal humeral fractures treated with locking plate

PURPOSE

The aim of this study is to understand whether the isokinetic strength could be a valid objective data of functional recovery evaluating a group of patients with proximal humeral fractures treated with open reduction and internal fixation with locking plate comparing the clinical and functional recovery (isokinetic strength) with the not involved side.

METHODS

Seventy patients underwent surgery with locking plate placement for proximal humeral fractures. The strength of each patient's shoulders, both involved and not involved, was evaluated using isokinetic tests and Constant-Murley score. Finally, the study included 48 patients and the mean follow-up of 33 months.

RESULTS

The functional outcome showed no significant differences between operated and not operated shoulder.

CONCLUSIONS

This study shows that the assessment of the force can be supported by use of tools such as the evaluation with isokinetic machines with the advantage of having, in this way, an objective data on the functional recovery.

LEVEL OF EVIDENCE

III.

Complication rates and outcomes stratified by treatment modalities in proximal humeral fractures: a systematic literature review from 1970-2009

Background

The optimal treatment of complex, displaced proximal humeral fractures is controversial. A systematic literature review of the time period from 1970 to 2009 was conducted. The purpose was to evaluate the clinical success and complications of the available treatment modalities to determine specific treatment recommendations for the different fracture patterns.

Methods

The databases (PubMed/EMBASE) were searched for the time period (01/1970–09/2009). Study quality, treatment modalities, classification, outcome scores and complications of 200 publications including 9377 patients were analyzed. Interventions were compared by analysis of variance with subsequent Tukey’s-test. Complication rates among methods were compared by using Pearson’s-chi-square-test and pairwise comparisons using Fisher’s-two-tailed-exact-test.

Results

Hemiarthroplasty, angle-stable plate and non-operative treatment were used for 63% of the follow-up-patients. For 3- and 4-part fractures, patients with hemiarthroplasty [3-Part: 56.4 (lower/upper 95% confidence interval (CI): 43.3-68.7); 4-Part: 49.4 (CI: 42.2-56.7)] received a lower score than different surgical head-preserving methods such as ORIF [3-Part: 82.4 (CI: 76.6-86.9); 4-Part: 83.0 (CI:78.7-86.6)], intramedullary nailing [3-Part: 79.1 (CI:74.0-83.4)] or angle-stable plates [4-Part: 66.4 (CI: 59.7-72.4)].

The overall complication rate was 56%. The most common complications were fracture-displacement, malunion, humeral head necrosis and malreduction. The highest complication rates were documented for conventional plate and hemiarthroplasty and for AO-C, AO-A, for 3- and 4-part fractures. Only 25% of the data were reported with detailed classification results and the corresponding outcome scores.

Discussion

Despite the large amount of patients included, it is difficult to determine adequate recommendations for the treatment of proximal humeral fractures because a relevant lack of follow-up data impaired subsequent analysis. For displaced 3- and 4-part fractures head-preserving therapy received better outcome scores than hemiarthroplasty. However, a higher number of complications occurred in more complex fractures and when hemiarthroplasty or conventional plate osteosynthesis was performed. Thus, when informing the patient for consent, both the clinical results and the possibly expected complications with a chosen treatment modality should be addressed.

Can the osteosynthesis with locking plates be a better treatment for unstable fractures of the proximal humerus?

PURPOSE

The purpose of this study is to review our experience with proximal humeral locking plates, including complications, functional outcomes, strength recovery and predictors of successful treatment.

METHODS

Seventy unstable proximal humeral fractures were treated with open reduction internal fixation (ORIF) with the use of locking proximal humerus plate. At an average follow-up of 31 months, the clinical and subjective outcomes were evaluated, and complication was analysed.

RESULTS

The average Constant score was 72. The mean disabilities of the arm, shoulder and hand score was 23. The average range of motion was as follows: mean range of anterior elevation and abduction 120°-150°; external rotation in abduction 64° and in adduction 44°; and internal rotation T12.

CONCLUSION

On the basis of the overall functional and clinical outcome obtained, it is possible to suggest that the ORIF of the proximal humerus fractures using locking plate represents a helpful option that can lead to a good clinical and functional outcome even in the most complex fractures.

Are polyaxially locked screws advantageous in the plate osteosynthesis of proximal humeral fractures in the elderly? A prospective randomized clinical observational study

OBJECTIVES

To evaluate the results of plate osteosynthesis using either polyaxial or nonpolyaxially locked screw-plate systems in proximal humeral fractures in the elderly.

DESIGN

Prospective, randomized.

SETTING

Level I trauma center.

METHODS

Fifty-six patients (older than 60 years) with isolated, displaced three- and four-part fractures were included. Twenty-five patients (median age, 75.5 years) were randomized to a polyaxial locking screw plate (Group 1), whereas 31 patients (median age, 72 years) were treated with a locking screw plate (Group 2). Follow-up evaluations were performed 3, 6, and 12 months postoperatively using the Simple Shoulder Test, Disabilities of the Arm, Shoulder and Hand score, and Constant score as well as radiographs. The results and the complications were compared between both groups.

RESULTS

Forty-eight patients were available for follow-up (Group 1, 20 of 25; Group 2, 28 of 31). The Simple Shoulder Test, Disabilities of the Arm, Shoulder and Hand, and Constant score improved significantly from 3 to 12 months and did not differ between groups. Twelve months after the index procedure, the Simple Shoulder Test score was 8.6 ± 3.2 points in Group 1 and 9.7 ± 1.8 points in Group 2. The Disabilities of the Arm, Shoulder and Hand score was 17.8 ± 16.2 in Group 1 and 15.7 ± 11.8 in Group 2. The mean Constant score amounted to 73% ± 17% in Group 1 and 81% ± 13% in Group 2. There were six complications in Group 1 and eight in Group 2.

CONCLUSIONS

Both the functional outcomes and the rate of complications after polyaxial locked plate osteosynthesis of proximal humeral fractures in elderly patients were comparable to those treated with nonpolyaxial implants. Despite the theoretical advantages of polyaxial locked plating in proximal humerus fractures, this study could not show a verifiable clinical advantage of these plates.

Mid-term results of internal fixation of proximal humeral fractures with the Philos plate

OBJECTIVE

To report our experience from the use of the Philos plate for the treatment of three- and four-part proximal humeral fractures and to investigate factors influencing the final outcome.

MATERIALS AND METHODS

Between April 2005 and September 2007, 29 Philos plates were implanted in 17 women and 12 men, with a mean age of 62.3 years (range: 28-80 years). Positioning of the plate was performed under fluoroscopic control, through a deltopectoral approach and with the patient in the beach chair position. 27 patients were available for follow-up (mean: 17.9 months; range: 12-39). Follow-up included plain shoulder radiographs and functional assessment with Constant-Murley score.

RESULTS

Healing of the fracture occurred uneventfully within 6 months. In three patients, humeral head collapsed due to aseptic necrosis after fracture healing and the plate had to be removed in two cases. In one patient, fracture healing occurred in >10 degrees varus displacement. The clinical result according to the Constant-Murley score was 86 points (range: 58-112).

CONCLUSIONS

Internal fixation with the Philos plate seems to be a reliable option in the operative treatment of upper end humeral fractures, especially in osteoporotic bone. It allows secure fracture fixation and quick shoulder mobilisation, while quick and uneventful fracture healing and very satisfactory clinical results are achieved.

Lessons learned from a case of proximal humeral locked plating gone awry

A 59-year-old woman underwent plate fixation of her 2-part anatomic neck proximal humerus fracture through an open anterolateral approach. The fixation subsequently failed, and the operation resulted in a dense axillary nerve palsy. Six weeks after her initial procedure, she was returned to the operating room. Exploration of the nerve revealed that it was compressed beneath the plate and irreparably damaged. Sural nerve cable grafting was required in an attempt to salvage deltoid function. The recent introduction of proximal humeral locking plates provides an opportunity for surgeons to reevaluate their methods of managing proximal humerus fractures. Indications for operative fixation have broadened, and a renewed interest in the anterolateral surgical approach has been reported. This case is the first description of an axillary nerve injury occurring in association with the open anterolateral approach when used for the treatment of a proximal humerus fracture and serves as a reminder that surgeons considering the use of a lateral approach must have a thorough understanding of axillary nerve anatomy. An additional review of the case provides a forum for discussion of the anterolateral approach to the proximal humerus and an opportunity to highlight the methods that can be used to optimize fixation when locked plates are employed. It must be emphasized that our enthusiasm for advances in technique and technology should not distract from basic surgical principles when treating these fractures.

[The cloverleaf plate for osteosythesis of humeral head fractures. Definition of the current position]

In this prospective study we evaluated the functional and radiological results obtained in 62 patients who had been treated for fracture of the humeral head by internal fixation with a cloverleaf plate. They were examined postoperatively, after 14 weeks and after an average follow-up of 75 weeks. Nine patients (14.5%) had dislocated 2-part fractures, 36 had 3-part fractures (58%; additional dislocations of the greater or lesser tubercle), 13 patients (21%) had 4-part fractures and 4 (5.6%) had luxation fractures of the humeral head. Early functional physiotherapy was started on the third day after surgery. The complications observed were: subcutaneous infection (2 cases; 3.2%), haematoma (2 cases; 3.2%), temporal paraesthesia of the axillary nerve (1 case; 1.6%). Only 4 (6.5%) patients suffered from necrosis of the humeral head (partial in 3, total in 1); in 2 cases (3.2%) we switched to a different procedure; in both these patients a humeral head prosthesis was implanted; in both these cases the clinical result was poor because of progressive varus dislocation. To improve mobility we performed arthrolysis in 8 cases (12.9%) and acromioplasty in 10 (16.1%), in addition to removing the plates after fracture consolidation confirmed by X-ray examination. In the present study those of our patients who had been treated with open reduction and internal fixation with a cloverleaf plate achieved average Neer scores of 77+/-13 and average Constant scores of 72.4+/-18, and the rates of complications or revisions were low. "Good" or "very good" results were obtained according to the Constant score in 59% of the treated patients. Even patients with complex 4-part fractures had average Constant scores of 72.7 points ("good"). The accuracy of the refixation of the greater tubercle, sufficiently low fixation of the cloverleaf plate and avoidance of varus position when the humeral head was repositioned were significant parameters influencing the functional outcome in our patients.

Internal fixation of proximal humerus fractures using the Polarus intramedullary nail

INTRODUCTION

It has been stated that proximal humeral fractures are the last unsolved fractures in orthopedics. In this study, we evaluate the results of the Polarus nail, in order to constitute to the controversial problem of the treatment of proximal humerus fractures.

PATIENTS AND METHODS

Between 2003 and 2005, 27 patients with severely displaced proximal humeral fractures were treated with the Polarus intramedullary system. The fractures were classified according to the Neer classification system. There were 16 2-part fractures and 11 3-part fractures. At the 12-months follow up we graded the clinical outcome of the patients according to the Neer scoring system.

RESULTS

The duration from time of injury to operation ranged from 1 to 6 days. The mean operative time was 55 min and no need of blood transfusion was recorded. Bony union was obtained in 27 patients. There were no cases of nonunion and the period from operation to the appearance of sufficient bridging callus on radiographs was 5-11 weeks (mean 6 weeks). In one patient, a backed-out proximal screw was recorded. Stiffness of the shoulder was seen in one patient and avascular necrosis of the head of humerus in another. Related to the clinical outcome, six patients had an excellent result, 15 patients had a satisfactory result, four patients had an unsatisfactory result, and two patients had a poor result. The 77.78% of the patients had an excellent or satisfactory clinical outcome. There was significant difference in the functional outcome between patients younger than 65 years (91.55) and those older than 65 years (80.22) (P < 0.05). No significant difference was recorded in the Neer score between the patients with a 2-part fracture and the patients with a 3-part fracture (80.18) (P > 0.05).

CONCLUSION

The Polarus nail is designed to provide stable fixation with a straightforward insertion and targeting procedure. The fact that 77.78% of the patients had an excellent or satisfactory clinical outcome, suggest that Polarus humeral rod system can be a worthy alternative to traditional operative methods for displaced proximal fractures of the humerus.

Ergebnisse nach Versorgung instabiler proximaler Humerusfrakturen mittels winkelstabiler Platte

BACKGROUND

Fixed-angle implants are being increasingly used in surgery of fractures of the proximal humerus. The aim of this retrospective investigation was to evaluate the outcome after fracture reduction utilizing a fixed-angle plate (Königsee).

MATERIALS AND METHODS

Between January 2003 and April 2004, 58 patients were operated, 52 of whom received a fixed-angle implant; 46 cases were harvested for a follow-up examination. Each patient was re examined clinically and radiologically at least 6 and 18 months after surgery. The functional outcome was evaluated using the Constant Score and the Simple Shoulder Test. The results were compared to results of other investigations.

RESULTS

The mean patient age was 68.8 years (34-94 years). Fractures were classified using the Neer Classification: 12 were classified as two-part, 25 as three-part, and 9 as four-part fractures. Three of the three-part and four of the four-part fractures were rated as luxation fractures. The overall functional outcome of all cases was good. More than 18 months after surgery the mean general "Constant Score" was 57; the mean side-related "Constant Score" was 89%. The Simple Shoulder Test revealed a pain-free range of motion in 41 (89.1%) of the individuals. The majority of the patients were satisfied with the results regarding remaining range of activity of the injured limb. In five cases significant complications occurred. In two cases the head of the humerus collapsed, and in one case a necrosis of the head occurred. In one individual the implant broke after an additional trauma. In this case a re-osteosynthesis utilizing a tibia plate was performed and the patient was excluded from further follow-up investigations. One soft tissue infection occurred after initial surgery.

CONCLUSION

It has been shown that results after fixation of proximal humerus fractures with fixed-angle implants are good. The functional outcome is good and complications are rare. Our results correlate with other investigations regarding fracture reduction using fixed-angle plates and nails.

[Operative treatment of proximal humeral fractures with helix wire]

BACKGROUND

Between 1 January 2000 and 31 December 2002, a total of 50 patients with a dislocated or unstable fracture of the proximal humerus were treated surgically with a titanium helix wire introduced retrogradely into the medullary cavity.

MATERIAL AND METHODS

Fracture classification showed 8 cases of a two-fragment fracture, 32 cases of a three-fragment fracture, and 10 cases of a so-called four-fragment fracture. A retrospective radiographic and medical review of all 50 patients showed postoperative complications in 24% of the cases; in 8 cases (16%) secondary loss of retention occurred with consecutive projection of the helix wires into the subacromial joint space. There were two cases each (4%) of perforation of the helix wire into the joint space without loss of retention and fracture dehiscence because of a blocking mechanism by the helix wire in the subcapital fracture gap. The postoperative revision rate was 18% (9/50) as a result. Of 50 patients with a titanium helix wire, 38 (76%) were reviewed after an average of 23 months (12-31). Radiologically partial necrosis of the head of the humerus was seen in two patients and there was necrosis of the head of the humerus with pseudarthrosis in one patient, which had a negative effect on the Constant score.

RESULTS

Because of a change of procedure (n=5) and intercurrent deaths (n=5) only 2 of 12 patients, in whom complications had occurred postoperatively, could be followed up clinically; the results of the follow-up are sure to be distorted by this selection effect. Of 38 patients, 32 (84%) showed very good to good results functionally; the average Constant score was 74 points and the average age- and sex-specific corrected score was 92%.

DISCUSSION

Thus, the procedure does not achieve better functional results compared to other rigid and semirigid internal fixation methods while it has a high complication and revision rate compared to other rigid and semirigid internal fixation methods. Moreover, early functional treatment is not possible so that the titanium helix wire represents a retention aid rather than stable internal fixation. Overall we cannot recommend the procedure for the operative management of proximal humerus fractures further and have abandoned it ourselves.

New trends in the treatment of proximal humerus fractures

For complex proximal humeral fractures, most authors agree on the importance of anatomic reduction and stable fixation to allow early range of motion. Currently a variety of techniques are used such as K-wires, t-plates, and primary prosthesis among others. However, no current treatment guidelines have been established. Newer implants provide greater angular stability, better biomechanical properties, and enhanced anchorage in these complex injuries. These implants therefore have a potential for achieving better results in treating complex fractures. We discuss current treatment concepts and focus on biomechanics and early results of new implants designed to provide angular stability.

LEVEL OF EVIDENCE

Expert Opinion, Level V. See the Guidelines for Authors for a complete description of levels of evidence.

[Results of the provision of unstable proximal humeral fractures in geriatric patients with a new angle stabilizing antegrade nail system]

Treating unstable proximal humeral fractures in elderly patients with osteoporosis and limited compliance is still demanding for trauma surgeons. The failure rate of operative treatment is high. We studied the use of a new antegrade intramedullary humeral nail with special locking bolts for head fixation. The first 41 procedures in 39 patients with a mean age of 81 years (61-102) were analyzed. Half of the patients were mentally deranged. There were 16 two-part, 22 three-part, and 3 four-part fractures of the humeral head treated. After closed or partial open reduction, antegrade nailing was performed via a delta split and limited incision of the rotator cuff. Greater and lesser tuberosities were fixed with screws through threaded holes of the proximal nail leading to high stability. Early functional active treatment was performed avoiding maximal rotation. Follow-up was 13 months (7-21 months). Clinical examination was performed in 32 cases. Four patients were questioned by phone. Three patients died (mean age: 92 years) before follow-up. The mean Constant score was 57+/-12. The mean age-related and side-related Constant scores were 86+/-17% and 90+/-7%. All fractures healed. Activities of daily life were possible in every case. There was only one loss of reduction after a fall out of bed. After hemiarthroplasty the patient was excluded from the study. One shaft fissure occurred during distal interlocking and healed uneventfully. Because of stable fixation, rehabilitation without immobilization was possible and led to good functional results. In comparison to common implants, the new antegrade intramedullary nail allowed a stable osteosynthesis in unstable proximal humeral fractures in old and very old patients with limited compliance without the usual implant-related complications.

Proximal humeral fractures: how stiff should an implant be? A comparative mechanical study with new implants in human specimens

BACKGROUND

The objective of this study was to determine the in vitro characteristics of the clinically used and newly developed implants for the stabilization of proximal humeral fractures under static and cyclic loading. The goal was to optimize implant stiffness for fracture stabilization even in weak bone stock.

METHODS

In a laboratory study using 35 fresh human humeri, the specimens were randomized into 5 groups, which included the clinically used humerus T-plate (HTP), the cross-screw osteosynthesis (CSO), the unreamed proximal humerus nail with spiral blade (UHN), the recently developed Synclaw Proximal Humerus Nail (Synclaw PHN) and the angle-stable Locking Compression Plate Proximal Humerus (LCP-PH). The implant stiffness was determined for three clinically relevant load cases: axial compression, torsion and varus bending. In addition, a cyclic varus-bending test was performed to determine the implant properties under cyclic loading.

RESULTS

In contrast to a rather elastic and minimally invasive implant(LCP-PH), the conventionally designed ones (Synclaw PHN, CSO, HTP, UHN) showed rather high stiffness values under static loading. In cyclic loading, a strong decrease in stiffness ( p<0.05) was found for the rigid implants HTP and UHN. In comparison with the other implants, only the elastic implant (LCP-PH) showed a significantly lower load reduction in a weak bone stock (17+/-6.2%).

CONCLUSION

The high initial stiffness of rigid implants led to an early loosening and failure of the implant-bone interface under cyclic loading. Implants with low stiffness and elastic characteristics, however, appear to minimize the peak stresses at the bone-implant interface, making them particularly suitable for fracture fixation in osteoporotic bone.