Rate of avascular necrosis and time to surgery in proximal humerus fractures

Risk factors for osteonecrosis of the humeral head after internal fixation of proximal humeral fractures: a systematic review and meta-analysis

BACKGROUND

Osteonecrosis of the humeral head (ONHH) is a severe complication after the internal fixation of proximal humeral fractures (IFPHF). The risk factors remain controversial though many studies have reported. In this research, meta-analysis was used to evaluate which surgeon-level factors can be modified to lower the risk and we hope to provide evidence-based support for preventing ONHH.

METHODS

Literature was retrieved from PubMed, Cochrane Library, Embase, Web of Science, and Scopus for eligible studies published up to January 2023. The pooled odds ratios (ORs) were calculated with their corresponding 95% confidence intervals (CIs) to evaluate. STATA 15.1 software was applied for data synthesis, sensitivity synthesis, and publication bias.

RESULTS

45 articles were published between 2000 and 2022, and 2482 patients were finally included. All articles were observational research, with 7 case-control studies and 38 cohort studies, and the Newcastle Ottawa Scale (NOS) score ranged from 7 to 9. The pooled results suggested that age (OR 0.32, 95% CI 0.14-0.74, P = 0.01), reduction quality (OR 0.08, 95% CI 0.01-0.44, P = 0.00), fracture type (OR 0.44, 95% CI 0.25-0.78, P = 0.01), surgical approach (OR: 4.06, 95% CI 1.21-13.61, P = 0.02) and fixation implant (OR = 0.68, 95% CI = 0.34-1.33, P = 0.02) were risk factors for ONHH after IFPHF. According to sensitivity analysis, Begg (P = 0.42) and Egger (P = 0.68) tests, the results were stable and exhibited no publication bias.

CONCLUSIONS

The study showed that age, reduction quality, fracture type, surgical approach and fixation implant were risk factors for ONHH after IFPHF, while gender, varus or valgus, timely operation, injured side, and the existence of medial support have little influence on ONHH, as they could not be considered risk factors and still need further investigations.

Assessment of surgical management for locked fracture-dislocations of the proximal humerus in patients of different ages

Background

Locked fracture-dislocation of the proximal humerus (LFDPH) is a very severe complex injury; neither arthroplasty nor internal plating are fully satisfactory. This study aimed to evaluate different surgical treatments for LFDPH to determine the optimal option for patients of different ages.

Methods

From October 2012 to August 2020, patients who underwent open reduction and internal fixation (ORIF) or shoulder hemiarthroplasty (HSA) for LFDPH were retrospectively reviewed. At follow-up, radiologic evaluation was performed to evaluate bony union, joint congruence, screw cut-out, avascular necrosis of the humeral head, implant failure, impingement, heterotopic ossification, and tubercular displacement or resorption. Clinical evaluation comprised the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire and Constant-Murley and visual analog scale (VAS) scores. Additionally, intraoperative and postoperative complications were assessed.

Results

Seventy patients (47 women and 23 men) with final evaluation results qualified for inclusion. Patients were divided into three groups: group A: patients aged under 60 years who underwent ORIF; group B: patients aged ≥60 years who underwent ORIF; and group C: patients who underwent HSA. At a mean follow-up of 42.6 ± 26.2 months, function indicators, namely shoulder flexion, and Constant-Murley and DASH scores, in group A were significantly better than those in groups B and C. Function indicators in group B were slightly but not significantly better compared with group C. Regarding operative time and VAS scores, there were no significant differences between the three groups. Complications occurred in 25%, 30.6%, and 10% of the patients in groups A, B, and C, respectively.

Conclusions

ORIF and HSA for LFDPH provided acceptable but not excellent results. For patients aged <60 years, ORIF might be optimal, whereas, for patients aged ≥60 years, both ORIF and HSA provided similar results. However, ORIF was associated with a higher rate of complications.

Severe Infraclavicular Displacement of a Proximal Humerus Fracture with Concomitant Olecranon Fracture in a Pediatric Patient

Proximal humerus fractures with severe medial displacement of the humeral head are rare in adults and especially so in children. Concomitant vascular/neurovascular injury is even more uncommon but must be considered as the associated complications can carry significant morbidity. We present a case of a 12-year-old transported to the ED after a mountain bike accident in which she lost control and hit a cement wall, injuring her left upper extremity (LUE). Despite a normal vascular/sensory exam, imaging demonstrated a left comminuted proximal humerus fracture with the humerus displaced medially into the thoracic inlet as well as concern for left subclavian vessel injury. Given the possibility of vascular injury and the severe humeral head displacement, she was taken to surgery with orthopedic and vascular surgical teams. Although surgical exploration did not reveal vascular injury, this case underlines the importance of maintaining a high index of suspicion for neurovascular injury with such fractures as prompt intervention may reduce the likelihood of complications. This case also underscores the need for further research into the management of pediatric proximal humerus fractures in early adolescence.

Incidence of avascular necrosis following biceps tenodesis during proximal humerus open reduction and internal fixation

Avascular necrosis (AVN) may occur in up to 77% of proximal humeral fractures and can cause fixation failure. Risk factors include fracture position, calcar length and medial hinge integrity. We routinely perform intra-articular biceps tenotomy with tenodesis at the level of pectoralis major to facilitate fragment identification and potentially ameliorate post-operative pain relief. Concern exists that tenotomising the biceps damages the adjacent arcuate artery, potentially increasing the rate of AVN. The purpose of this study was to evaluate whether biceps tenodesis is associated with an increased risk of radiographically evident humeral head AVN. 61 fractures surgically treated over a 52-month period were retrospectively reviewed and radiographically assessed in accordance with Neer’s classification, calcar-length and medial hinge integrity. 40, 20 and 1 were four-, three- and two-part fractures respectively. 37 had a calcar-length less than 8mm and 26 suffered loss of the medial hinge. The median radiographic follow-up was 23 months. There was radiographic evidence of humeral head AVN in only one case, comparing favourably to rates quoted in current literature. In our experience, intra-articular biceps tenotomy with the deltopectoral approach was thus not associated with a significantly increased risk of humeral head AVN, even in complex four-part fractures.

Protective and Risk Factors for Humerus Head Necrosis After Proximal Humerus Fracture Treated with Internal Locking Plate

BACKGROUND

Proximal humerus fractures (PHF) are common and lead to post-traumatic humerus head necrosis (HHN) in 3-35% after ORIF with an internal locking plate. Few studies focus on this condition and risk factors remain a discussion topic. Hertel's criteria for initial head ischemia right after fracture (fracture complexity, medial hinge displacement and short metaphyseal head extension) have recently been correlated to HHN, but there is still a clear lack of evidence on the topic. Due to its anatomical similarities to the proximal femur, some authors argue that PHF may as well benefit from early surgery to avoid head necrosis.

METHODS

In this 10-year retrospective study, we assessed 305 patients from a single center. All cases were treated with a PHILOS plate through a deltopectoral approach. The mean follow-up time was 467 days. The primary endpoint was HHN.

RESULTS

HHN was diagnosed in 12 patients (4%), 10 of which were diagnosed within the first year and one case 4 years after surgery. A positive correlation (p < 0.04) was found between HHN and fracture type (both in AO and Neer's classification), initial neck-shaft-angle (NSA) and metaphyseal head extension (MHE). Medial hinge displacement (MHD) occurred in all HHN cases. Achieving perfect reduction (< 2 mm dislocation) was relevant to avoiding HHN (p = 0.035). Although HHN developed in 32% of the high risk cases (four-part fractures with a short MHE), it was completely avoided (0%) when perfect reduction was achieved. Time until surgery after admission was neither a protective nor a risk factor for HHN.

CONCLUSION

We conclude that fracture complexity (four-part and C-fractures) as well as disruption of the medial hinge with a metaphyseal head extension smaller than 8 mm are relevant risk factors for humerus head necrosis. A combination of these criteria generated an high risk pattern with a 32% rate of HHN. Though often difficult to achieve, perfect reduction was a clear protective factor and reduced HHN to 0%. Perfect reduction may be key to inosculation and, therefore, salvage of the humerus head, especially in high risk cases. Surgery timing did not correlate with HHN.

LEVEL OF EVIDENCE

Level 3, retrospective cohort study.

Does time to surgery affect patient-reported outcome in proximal humeral fractures? A subanalysis of the PROFHER randomized clinical trial

Aims

The aim of this study was to explore whether time to surgery affects functional outcome in displaced proximal humeral fractures

Methods

A total of 250 patients presenting within three weeks of sustaining a displaced proximal humeral fracture involving the surgical neck were recruited at 32 acute NHS hospitals in the United Kingdom between September 2008 and April 2011. Of the 125 participants, 109 received surgery (fracture fixation or humeral head replacement) as per randomization. Data were included for 101 and 67 participants at six-month and five-year follow-up, respectively. Oxford Shoulder Scores (OSS) collected at six, 12, and 24 months and at three, four, and five years following randomization was plotted against time to surgery. Long-term recovery was explored by plotting six-month scores against five-year scores and agreement was illustrated with a Bland-Altman plot.

Results

The mean time from initial trauma to surgery was 10.5 days (1 to 33). Earlier surgical intervention did not improve OSS throughout follow-up, nor when stratified by participant age (< 65 years vs ≥ 65 years) and fracture severity (one- and two-part vs three- and four-part fractures). Participants managed later than reported international averages (three days in the United States and Germany, eight days in the United Kingdom) did not have worse outcomes. At five-year follow-up, 50 participants (76%) had the same or improved OSS compared with six months (six-month mean OSS 35.8 (SD 10.0); five-year mean OSS 40.1 (SD 9.1); r = 0.613). A Bland-Altman plot demonstrated a positive mean difference (3.3 OSS points (SD 7.92)) with wide 95% limits of agreement (-12.2 and 18.8 points).

Conclusion

Timing of surgery did not affect OSS at any stage of follow-up, irrespective of age or fracture type. Most participants had maximum functional outcome at six months that was maintained at five years. These findings may help guide providers of trauma services on surgical prioritization. Cite this article: Bone Joint J 2020;102-B(1):33–41

An anatomical investigation into the blood supply of the proximal humerus: surgical considerations for rotator cuff repair

Background

The purpose of this study was to investigate the blood supply of the humeral head (HH) originating from the anterior (ACHA) and posterior circumflex humeral arteries (PCHA).

Methods

Formalin preserved specimens were used to measure ACHA length, ACHA length in the bicipital groove (BG), the length of the ascending branch of the ACHA, the penetration point of the ascending branch of the ACHA at the greater tuberosity (GT), and the penetration point of the ascending branch PCHA at the GT. Fresh specimens were used to identify the intraosseous vascular network by both the ACHA and PCHA by injecting a contrast medium using a high-resolution microfocus computed tomography. Specimens were then dissected to expose where the branches of the ACHA and PCHA penetrate the bone, and a small section of the medial head was removed to visualize dye penetration of the cancellous bone.

Results

Seven variations for the course of the ACHA were observed. In 36%, the ACHA runs posterior to the BG and posterior to the long head of biceps tendon, and splits into the anterolateral ascending and descending branch. The ascending branch enters the medial wall of the GT. Microfocus computed tomography demonstrated that the intraosseous branch of the ascending branch of the ACHA runs within the GT in a medial direction from its penetration point just along the lateral edge of the BG. Intraosseous accumulation of contrast within the GT supply occurs more toward the inferior aspect of the HH, and the anterior-superior and superior-medial aspect of the HH is not perfused. This region is a high-risk zone for avascular necrosis.

Conclusion

The results of this study suggest that 7 variations for the course of the ACHA exist. These variations and the interruption of the intraosseous arterial network in the GT with surgery and suture anchor placement result in a high-risk zone in the superomedial aspect of the humeral head overlapping with the area where early aseptic necrosis is identified.

Rate of avascular necrosis after fracture dislocations of the proximal humerus: Timing of surgery

Background

Avascular necrosis (AVN) of the humeral head is a severe complication after proximal humerus fracture dislocations, and leads to a poorer clinical outcome and subsequent revision surgeries. The aim of the current study was to analyze the influence of time to surgery on the AVN rate after locked plating of dislocation fractures of the proximal humerus.

Patients and methods

This retrospective study included 30 patients with a mean age of 63 ± 14 years with dislocation fractures of the proximal humerus type B3 or C3 according the AO/OTA classification. The rates of AVN of the humeral head were determined clinically and radiographically. In addition, the clinical outcome was determined using the Constant score (CS), the age- and sex-adjusted Constant score (CS%), Disabilities of the Arm, Shoulder, and Hand (DASH) score, the range of motion, and complication and revision rates. Patients were subdivided into groups of subjects operated on early (≤48 h after trauma) and those with late surgery (>48 h after trauma), and the relative risk (RR) for complications and revisions was determined for both groups.

Results

After a mean follow-up of 37 months (range: 12-66 month) the mean CS% was 60 ± 24 and the mean DASH score was 32 ± 24 points. Ten patients (33%) developed a symptomatic AVN, and ten patients underwent revision surgery. Early surgery was performed on 25 patients while five patients underwent late surgery. After late surgery, all five patients developed AVN, and patients had a fivefold increased RR for AVN (p = 0.002) and subsequent associated surgical revision (RR = 3.3, p = 0.031).

Conclusion

In fracture dislocations of the proximal humerus, early surgery within 48 h of trauma significantly decreases the risk of AVN and subsequent surgery.