Ergebnisse nach Versorgung instabiler proximaler Humerusfrakturen mittels winkelstabiler Platte

Fractures of the proximal humerus

Fractures of the proximal humerus have been diagnosed and managed since the earliest known surgical texts. For more than four millennia the preferred treatment was forceful traction, closed reduction, and immobilization with linen soaked in combinations of oil, honey, alum, wine, or cerate. The bandages were further supported by splints made of wood or coarse grass. Healing was expected in forty days. Different fracture patterns have been discussed and classified since Ancient Greece. Current classification of proximal humeral fractures mainly relies on the classifications proposed by Charles Neer and the AO/OTA classification. Since the late 1980's it has been known that intra- and inter-observer variation was high within the two systems. I conducted a series of observer studies to qualify the disagreement further and to study to what extent improvement of agreement could be obtained. No clinically significant differences in observer agreement were found at different levels of clinical experience, by reducing the number of categories, or by adding high quality radiographs, CT or 3D CT scans. A consistently low agreement on the Neer classification within and between untrained orthopaedic doctors was found. However, we also found that inter-observer agreement on treatment recommendation was higher than the agreement on the Neer classification. In a randomized trial we found that agreement could improve significantly by training of doctors, especially among specialists. However, classification of proximal humeral fractures remains a challenge for the conduct, reporting, and interpretation of clinical trials. The evidence for the benefits of surgery in complex fractures of the proximal humerus is weak. In three systematic reviews I studied the outcome after locking plate osteosynthesis or reverse arthroplasty in complex fractures patterns. No randomized trials or well-conducted comparative studies were identified. High failure rates suggest that the use of these implants for complex fractures of the humerus should not be used outside clinical protocols. I recommend the conduct of randomized trials, and a design of such study is proposed.

Benefits and harms of locking plate osteosynthesis in intraarticular (OTA Type C) fractures of the proximal humerus: a systematic review

INTRODUCTION

Locking plate osteosynthesis of proximal humeral fractures are widely recommended and used, even in complex intraarticular fracture patterns such as AO/OTA Type C fractures. We systematically reviewed clinical studies assessing the benefits and harms of osteosynthesis with angle stable plates in AO/OTA Type C fractures of the proximal humerus.

METHODS

We conducted an iterative search in PubMed, Embase, Cochrane Library, Web of Science, Cinahl, and PEDro in all languages from 1999 to November 2010. Eligible studies should study the outcome for Type C fractures after primary osteosynthesis with locking plate within two weeks of injury, and a follow-up period of six months or more. Patients should be evaluated with the Constant-Murley Score (CS). Two observers extracted data independently.

RESULTS

Twelve studies and 282 Type C fractures were included. Results were categorised according to study type and synthesised qualitatively. No randomised clinical trials were identified. Two comparative, observational studies reported a mean CS of 71 (relative to contralateral shoulder) and 75 (non-adjusted Constant Score) for Type C fractures. For all studies mean non-adjusted CS ranged from 53 to 75. Mean age- and sex-adjusted CS ranged from 60 to 88. Mean CS relative to the contralateral shoulder ranged from 71 to 85. The most common complications were avascular necrosis (range, 4-33%), screw perforations (range, 5-20%), loss of fixation (range, 3-16%), impingement (range, 7-11%) and infections range 4-19%. Reoperation rate ranged from 6 to 44%.

CONCLUSIONS

Insufficient study designs and unclear reporting preclude safe treatment recommendations. Complication and reoperation rates were unexpected high. Based on the studies included we cannot routinely recommend the use of locking plates in AO/OTA Type C fractures.

Minimally invasive polyaxial locking plate fixation of proximal humeral fractures: a prospective study

BACKGROUND

The surgical treatment for displaced humeral head fractures overlooks a broad variety of surgical techniques and implant systems. A standard operative procedure has not yet been established. In this article, we report our experience with a second-generation locking plate for the humeral head fracture that is applied in a standardized nine-step minimally invasive surgical technique (MIS).

METHODS

In a prospective study from May 2008 until November 2009, a cohort of 79 patients with 80 proximal humerus fractures were operated in a MIS procedure using a polyaxial locking plate. Follow-up examination at 6 weeks and 6 months postoperative included radiologic examinations and a clinical outcome analysis by the Constant Score, the Visual Analog Scale for pain, and the Daily Activity Score.

RESULTS

The mean patient age was 65.5 years ± 19 years. According to the Neer classification, there were 18 (22.5%) two-part (Neer III), 48 (60%) three-part (Neer IV), and 14 (17.5%) four-part fractures (Neer IV/V). The operation time averaged 65.6 minutes ± 27 minutes. In 13 patients (16.3%), revision was necessary because of procedure-related complications. After 6 months, the Visual Analog Scale for pain was 2.7 ± 1.6 and the Daily Activity Score showed 19.6 ± 6 points. The average age-related Constant Score after 6 months was 67.5 ± 24 points.

CONCLUSIONS

MIS surgery of displaced humeral head fractures can be performed in all types of humeral head fractures leading to low complication rates and good clinical outcome. A standardized stepwise procedure in fracture reduction and fixation is recommended to achieve reliable good results.

Locking plate osteosynthesis in displaced 4-part fractures of the proximal humerus

BACKGROUND AND PURPOSE

There is considerable uncertainty about the optimal treatment of displaced 4-part fractures of the proximal humerus. Within the last decade, locking plate technology has been considered a breakthrough in the treatment of these complex injuries.

METHODS

We systematically identified and reviewed clinical studies on the benefits and harms after osteosynthesis with locking plates in displaced 4-part fractures.

RESULTS

We included 14 studies with 374 four-part fractures. There were 10 case series, 3 retrospective observational comparative studies, 1 prospective observational comparative study, and no randomized trials. Small studies with a high risk of bias precluded reliable estimates of functional outcome. High rates of complications (16-64%) and reoperations (11-27%) were reported.

INTERPRETATION

The empirical foundation for the value of locking plates in displaced 4-part fractures of the proximal humerus is weak. We emphasize the need for well-conducted randomized trials and observational studies.

Monoaxial versus polyaxial locking systems: a biomechanical analysis of different locking systems for the fixation of proximal humeral fractures

OBJECTIVE

The development of locking plate systems has led to polyaxial screws and new plate designs. This study compares monoaxial head locking screws (PHILOS© by Synthes) and a new generation of polyaxial locking screws (NCB-LE© by Zimmer) with respect to biomechanical stability.

METHODS

On nine pairs of randomised formalin fixed humerus specimens, standardised osteotomies and osteosyntheses with nine monoaxial (group A) und nine polyaxial (group B) plate/screw systems were performed. A material testing machine by Instron (M-10 14961-DE) was used for cyclic stress tests and crash tests until defined breakup criteria as endpoints were reached.

RESULTS

After axial cyclic stress 200 times at 90 N, plastic deformation was 1.02 mm in group A and 1.25 mm in group B. After the next cycle using 180 N the additional deformation averaged 0.23 mm in group A and 0.39 mm in group B. The deformation using 450 N was 0.72 mm in group A compared to 0.92 mm in group B. The final full power test resulted in a deformation average of 0.49 mm in group A and 0.63 mm in group B after 2,000 cycles using 450 N. When reaching the breakup criteria the plastic deformation of the NCB plate was 9.04 mm on average. The PHILOS plate was similarly deformed by 9.00 mm. As a result of the crash test, in group A the screws pulled out of the humeral head four times whereas the shaft broke one time and another time the implant was ripped out. The gap was closed four times. In group B, there were three cases of screw cut-through, four shaft fractures/screw avulsions from the shaft and two cases of gap closure.

CONCLUSION

The two systems resist the cyclic duration tests and the increasing force tests in a similar manner. The considerable clinical benefits of the polyaxial system are enhanced by equal biomechanical performance.

Monoaxial versus polyaxial screw insertion in angular stable plate fixation of proximal humeral fractures: radiographic analysis of a prospective randomized study

BACKGROUND

Monoaxial and polyaxial screw insertion are used in angular stable plating of displaced proximal humeral fractures. Aim of the study was to compare both fixation techniques by radiographic evaluation.

METHODS

Prospective randomized treatment with monoaxial or polyaxial screw insertion in angular stable anatomic preshaped plates of displaced proximal humeral fractures. Analysis of standardized true anterior-posterior (true a.p.) and outlet-view radiographs at 1 day, 6 weeks, 3 months, and 6 months after surgery by two radiologists with respect to radiographic evidence of secondary varus displacement, cut out of screws, osteonecrosis, and hardware failure. Secondary varus displacement was defined as a varus decrease of the humeral head-shaft angle of > 10 degree in true a.p. radiographs.

RESULTS

Sixty-six consecutive patients (48 women, [72.7%]; 18 men, [27.3%]; mean age 67.7 years [95% CI, 63.9-71.6]) with displaced proximal humeral fractures were evaluated in this study. Nineteen patients (29%) showed secondary varus displacement of > 10-degree angle. In 6 cases (9%), intra-articular cut out of screws was found. Furthermore, 1 case (2%) of nonunion was observed. No relationship between monoaxial and polyaxial screw insertion was found regarding occurrence of secondary varus displacement (monoaxial, 11/polyaxial, 8; p = 0.91) or screw cut out (monoaxial, 4/polyaxial, 2; p = 0.64). Prevalence of secondary varus displacement and hardware cut out was related to patients age (p = 0.02) and fracture pattern, according to Neer- and AO/OTA-classification (p < 0.001). The average immediate postoperative head-shaft angle was 135.2 degrees (CI, 132.3-138.1) in the group without radiographic complication, compared with 126.7-degree angle (CI, 123.6-129.7) among those with secondary varus displacement of > 10-degree angle and screw cut out (p < 0.001). Furthermore, in cases of an immediate postoperative head-shaft angle of < 130 degrees, there was a 48% incidence of secondary varus dislocation (n = 13) versus 15% in cases with a head-shaft angle > 130 degrees (n = 6, p = 0.004).

CONCLUSION

Monoaxial and polyaxial screw insertion allow for mechanical stabilization in angular stable plating of unstable proximal humerus fractures. Radiographic evidence of secondary varus displacement of > 10-degree angle and screw cut out was seen similarly often in both fixation techniques. To avoid secondary varus displacement and screw cut out, restoration of a humeral head-shaft angle of > 130 degrees seems to be important in monoaxial and polyaxial fixation of proximal humeral fractures.

Surgical treatment of two-part fractures of the proximal humerus: comparison of fixed-angle plate osteosynthesis and Zifko nails

INTRODUCTION

Closed reduction and percutaneous pinning using Zifko nails offer the advantage of a minimal soft-tissue dissection but have been criticised for limited stability and secondary fracture dislocation. Angular stable plate osteosynthesis enables anatomic reduction, but carries the risk of soft tissue traumatisation and consecutive humeral head necrosis. The present study compares the clinical and radiological outcome of patients with dislocated two-part fractures of the proximal humerus, who were treated with either Zifko nails or angular stable plate fixation.

MATERIAL AND METHODS

A matched-pair analysis was performed and patient groups were matched according to age (3 years), sex and fracture type. As many as 11 pairs of patients with a minimum follow-up of 3 years were formed and investigated radiographically and clinically using the Constant score (CS) and the visual analogue scale (VAS) for the patients' satisfaction.

RESULTS

At the time of follow-up, the absolute CS was 83 points in the PHP group and 78 points in the Zifko group (n.s.). Neither in the age and gender-corrected CS was found a significant difference between the study groups (PHP 104 29, Zifko 95 17, n.s.) nor in terms of subjective patient satisfaction (PHP 6.54; Zifko 7.8, n.s.). The complication rate was also comparable in both groups.

CONCLUSION

In conclusion, Zifko nailing represents a cost-effective minimally invasive surgical method with a complication rate and clinical outcome comparable to that after angular stable osteosynthesis by angular stable plate fixation in the treatment of two-part fractures of the proximal humerus.

Minimal invasive fixation of proximal humeral fractures with an intramedullary nail: good results in elderly patients

OBJECTIVE

To report on the results of a minimally invasive technique for the fixation of displaced proximal humeral fractures with a locked intramedullary nail.

PATIENTS AND METHODS

All consecutive patients treated with a T2 intramedullary nail between 2004 and 2007 were evaluated. Thirty-three patients were included [mean age 78, m:f ratio (1:4)]. Fracture characteristics were classified according to AO and Neer (eighteen 2-part, eleven 3-part, five 4-part fractures).

RESULTS

Functional outcome (Constant Score) was excellent in nine, satisfactory in eight and poor in three patients. Subjective outcome was satisfactory to good for patients with 2-part and 3-part fractures but poor for 4-part fractures. Major complications comprised four fixation failures, two cases of impingement and one deep infection.

CONCLUSIONS

Minimally invasive fixation of displaced 2-part and 3-part humeral fractures in an elderly population shows satisfactory to excellent results in 80% of patients.

Is locking nailing of humeral head fractures superior to locking plate fixation?

The optimal surgical treatment of displaced proximal humeral fractures is controversial. New implants providing angular stability have been introduced to maintain the intraoperative reduction. In a multi-institutional study, we prospectively enrolled and followed 152 patients with unilateral displaced and unstable proximal humeral fractures treated either with an antegrade angular and sliding stable proximal interlocking nail or an angular stable plate. Fractures were classified according to the Neer four-segment classification. Clinical, functional, and radiographic followups were performed 3, 6, and 12 months after surgery. Absolute and relative (to the contralateral shoulder) Constant-Murley scores were used to assess postoperative shoulder function. Using age, gender, and fracture type, we identified 76 pairs (152 patients) for a matched-pairs analysis. Relative Constant-Murley scores 12 months after treatment with an angular and sliding stable nail and after plate fixation were 81% and 77%, respectively. We observed no differences between the two groups. Stabilization of displaced proximal humeral fractures with either an angular stable intramedullary or an extramedullary implant seems suitable with both surgical treatment options.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Analysis of efficacy and failure in proximal humerus fractures treated with locking plates

OBJECTIVE

The purpose of this study was to determine the efficacy of proximal humerus locking plates (PHLP) and to clarify predictors of loss of fixation.

DESIGN

Retrospective review of patients with proximal humerus fractures fixed with a PHLP.

SETTING

Five Level 1 trauma centers.

PATIENTS

One hundred fifty-three patients (111 female, 42 male) 18 years or older with a displaced fracture or fracture-dislocation of the proximal humerus treated with a PHLP between January 1, 2001 and July 31, 2005.

INTERVENTION

Demographic data, trauma mechanism, surgical approach, and perioperative complications were collected from the medical records. Fracture classification according to the AO/OTA, radiographic head-shaft angle, and screw tip-articular surface distance in true anteroposterior (AP) and axillary lateral radiographs of the shoulder were measured postoperatively. Varus malreduction was defined as a head-shaft angle of <120 degrees.

MAIN OUTCOME MEASUREMENTS

Statistical analysis was done to establish correlations between loss of fixation and postoperative head-shaft angle in the true AP radiograph, patient age, fracture type, trauma mechanism, number of locking head screws, and type of plate.

RESULTS

The mean age was 62.3 +/- 15.4 years (22-92) and the mean injury severity score (ISS) was 9.5 +/- 10.16 (4-57; n = 73). The surgical approach was deltopectoral (90.2%) or transdeltoid (9.8%). No intraoperative complications were reported. The mean postoperative head-shaft angle was 130 degrees (95 degrees to 160 degrees; SD = 13). The overall incidence of loss of fixation was 13.7%. There was a statistically significant association between varus reduction (<120 degrees) and loss of fixation (30.4% when the head-shaft angle was <120 degrees versus 11% when the head-shaft angle was > or =120 degrees; P = 0.02).

CONCLUSION

This series presents the experience using PHLP in 5 Level 1 trauma centers. There were no intraoperative complications related to the locking plate systems. Despite the use of fixed-angle devices, loss of fixation occurred, primarily in the presence of varus malreduction. Our findings suggest that avoiding varus should substantially decrease the risk of postoperative failures.

Arthroscopical Findings after Antegrade Nailing of a Proximal Humeral Fracture : Case Report and Review of the Literature

Proximal humeral fractures represent up to five percent of all fractures in adults, commonly found in elderly patients. The final functional results after different operative procedures are among other factors dependent on whether or not a rotator cuff lesion is pre-existent, prior to the fracture, and how its surgical therapy is carried out. However, to what extent prior rotator cuff tears in this special patient group contribute to the functional outcome remains widely unclear. In our institution antegrade intramedullary nailing is the treatment of choice for proximal humeral fractures. One critical point of this technique is the unavoidable split of the rotator cuff on the approach to the proximal humerus and the insertion of the nail through the incised cuff. We report on a case of an impingement after antegrade intramedullary nailing of a proximal humeral fracture. Diagnostic glenohumeral arthroscopy revealed neither a residual lesion of the former rotator cuff incision nor a chondral lesion at the former insertion site of the nail. In the same session subacromial decompression and a nettoyage of adhesions were performed. We assume that splitting the rotator cuff for the insertion of an antegrade nail in a proximal humeral fracture is less relevant than previously assumed and described.

The importance of medial support in locked plating of proximal humerus fractures

OBJECTIVES

The purpose of this study was to determine what factors influence the maintenance of fracture reduction after locked plating of proximal humerus fractures, and particularly the role of medial column support.

SETTING

University medical center.

INTERVENTION

Thirty-five patients who underwent locked plating for a proximal humerus fracture were followed up until healing. For the initial and final radiographs, 2 lines were drawn perpendicular to the shaft of the plate, one at the top of the plate and one at the top of the humeral head, and the distance between them was measured as an indicator of loss of reduction. Medial support was considered to be present if the medial cortex was anatomically reduced, if the proximal fragment was impacted laterally in the distal shaft fragment, or if an oblique locking screw was positioned inferomedially in the proximal humeral head fragment.

MAIN OUTCOME MEASUREMENTS

Multivariate linear regressions were performed to determine the effects that age, sex, fracture type, cement augmentation, and medial support had on loss of reduction.

RESULTS

The presence of medial support had a significant effect on the magnitude of subsequent reduction loss (P < 0.001). Age, sex, fracture type, or cement augmentation had no effect on maintenance of reduction. Eighteen patients were determined to have adequate mechanical medial support (+MS group), and the remaining 17 patients did not have medial support (-MS group). In the +MS group, the average loss of humeral head height was 1.2 mm, and 1 case of articular screw penetration occurred that required removal. In the -MS group (without an appropriately placed inferomedial oblique screw and either nonanatomic humeral head malreduction with lateral displacement of the shaft or medial comminution), loss of humeral height averaged 5.8 mm (P < 0.001). There were 5 cases in this group in which screw penetration of the articular surface occurred (P = 0.02), 2 of which required reoperation for removal. All fractures in both groups healed without delay, and none required revision to arthroplasty.

CONCLUSIONS

Achieving mechanical support of the inferomedial region of the proximal humerus seems to be important for maintaining fracture reduction. Locked plates in general do not appear to be a panacea for these fractures and are unable to support the humeral head alone from a lateral tension-band position. However, there are several factors that are in the surgeon's control that may improve the mechanical environment. Achieving an anatomic or slightly impacted stable reduction, as well as meticulously placing a superiorly directed oblique locked screw in the inferomedial region of the proximal fragment, may achieve more stable medial column support and allow for better maintenance of reduction.