Wide Range in Complication Rates Following Elbow Arthroscopy in Adult and Pediatric Patients: A Systematic Review

PURPOSE

To perform a systematic review of complications associated with elbow arthroscopy in adults and children.

METHODS

A literature search was performed in the PubMed, EMBASE, and Cochrane databases. Studies reporting complications or reoperations after elbow arthroscopy with at least 5 patients were included. Based on the Nelson classification, the severity of complications was categorized as minor or major. Risk of bias was assessed using the Cochrane risk-of-bias tool for randomized clinical trials, and nonrandomized trials were assessed using the Methodological Items for Non-randomized Studies (MINORS) tool.

RESULT

A total of 114 articles were included with 18,892 arthroscopies (16,815 patients). A low risk of bias was seen for the randomized studies and a fair quality for the nonrandomized studies. Complication rates ranged from 0% to 71% (median 3%; 95% confidence interval [CI], 2.8%-3.3%), and reoperation rates from 0% to 59% (median 2%; 95% CI, 1.8%-2.2%). A total of 906 complications were observed, with transient nerve palsies (31%) as the most frequent complication. According to Nelson classification, 735 (81%) complications were minor and 171 (19%) major. Forty-nine studies reported complications in adults and 10 studies in children, showing a complication rate ranging from 0% to 27% (median 0%; 95% CI, 0%-0.4%) and 0% to 57% (median 1%; 95% CI, 0.4%-3.5%), respectively. A total of 125 complications were observed in adults, with transient nerve palsies (23%) as the most frequent complication, and 33 in children, with loose bodies after surgery (45%) as the most frequent complication.

CONCLUSIONS

Predominantly low-level evidence studies demonstrate varying complication rates (median 3%, range 0%-71%) and reoperation rates (median 2%, range 0%-59%) after elbow arthroscopy. Higher complication rates are observed after more complex surgery. The incidence and type of complications can aid surgeons in patient counseling and refining surgical techniques to further reduce the complication rates.

LEVEL OF EVIDENCE

Level IV; systematic review of Level I-IV studies.

Greater radial tuberosity size is associated with distal biceps tendon rupture: a quantitative 3-D CT case-control study

PURPOSE

During pronation, the distal biceps tendon and radial tuberosity internally rotate into the radioulnar space, reducing the linear distance between the radius and ulna by approximately 50%. This leaves a small space for the distal biceps tendon to move in and could possibly cause mechanical impingement or rubbing of the distal biceps tendon. Hypertrophy of the radial tuberosity potentially increases the risk of mechanical impingement of the distal biceps tendon. The purpose of our study was to determine if radial tuberosity size is associated with rupturing of the distal biceps tendon.

METHODS

Nine patients with a distal biceps tendon rupture who underwent CT were matched 1:2 to controls without distal biceps pathology. A quantitative 3-dimensional CT technique was used to calculate the following radial tuberosity characteristics: 1) volume in mm³, 2) surface area in mm², 3) maximum height in mm and 4) location (distance in mm from the articular surface of the radial head).

RESULTS

Analysis of the 3-dimensional radial tuberosity CT-models showed larger radial tuberosity volume and maximum height in the distal biceps tendon rupture group compared to the control group. Mean radial tuberosity volume in the rupture-group was 705 mm³ (SD: 222 mm³) compared to 541 mm³ (SD: 184 mm³) in the control group (p = 0.033). Mean radial tuberosity maximum height in the rupture-group was 4.6 mm (SD: 0.9 mm) compared to 3.7 mm (SD: 1.1 mm) in the control group, respectively (p = 0.011). There was no statistically significant difference in radial tuberosity surface area (ns) and radial tuberosity location (ns).

CONCLUSION

Radial tuberosity volume and maximum height were significantly greater in patients with distal biceps tendon ruptures compared to matched controls without distal biceps tendon pathology. This supports the theory that hypertrophy of the radial tuberosity plays a role in developing distal biceps tendon pathology.

LEVEL OF EVIDENCE

Level III.

Radial nerve palsy associated with closed humeral shaft fractures: a systematic review of 1758 patients

BACKGROUND AND PURPOSE

Humeral shaft fractures are often associated with radial nerve palsy (RNP) (8-16%). The primary aim of this systematic review was to assess the incidence of primary and secondary RNP in closed humeral shaft fractures. The secondary aim was to compare the recovery rate of primary RNP and the incidence of secondary RNP between operative and non-operative treatment.

METHODS

A systematic literature search was performed in 'Trip Database', 'Embase' and 'PubMed' to identify original studies reporting on RNP in closed humeral shaft fractures. The Coleman Methodology Score was used to grade the quality of the studies. The incidence and recovery of RNP, fracture characteristics and treatment characteristics were extracted. Chi-square and Fisher exact tests were used to compare operative versus non-operative treatment.

RESULTS

Forty studies reporting on 1758 patients with closed humeral shaft fractures were included. The incidence of primary RNP was 10%. There was no difference in the recovery rate of primary RNP when comparing operative treatment with radial nerve exploration (98%) versus non-operative treatment (91%) (p = 0.29). The incidence of secondary RNP after operative and non-operative treatment was 4% and 0.4%, respectively (p < 0.01).

INTERPRETATION

One-in-ten patients with a closed humeral shaft fracture has an associated primary RNP, of which > 90% recovers without the need of (re-)intervention. No beneficial effect of early exploration on the recovery of primary RNP could be demonstrated when comparing patients managed non-operatively with those explored early. Patients managed operatively for closed humeral shaft fractures have a higher risk of developing secondary RNP.

LEVEL OF EVIDENCE

Level IV; Systematic Review.

Arthroscopic localization of the ulnar nerve behind the medial capsule is unreliable

Purpose

Ulnar nerve injury is the most common neurologic complication of elbow arthroscopy. The purpose of this cadaveric study was to quantify the ability of surgeons to locate the ulnar nerve behind the posteromedial capsule during elbow arthroscopy using sole arthroscopic vision.

Methods

Twenty-one surgeons were asked to pin the ulnar nerve at the medial gutter and the posteromedial compartment using arthroscopic visualization of the medial capsule only. Pinning of the ulnar nerve was performed from extra-articular. Then, the cadaveric specimens were dissected and the shortest distances between the pins and ulnar nerve measured.

Results

Median pin-to-nerve distances at the medial gutter and posteromedial compartment were 0 mm (interquartile range [IQR], 0-3 mm) and 2 mm (IQR, 0-6 mm), respectively. The ulnar nerve was pinned by 11/21 surgeons (52%) at the medial gutter, and 7/21 surgeons (33%) at the posteromedial compartment. Three of 21 surgeons (14%) pinned the ulnar nerve at both the medial gutter and the posteromedial compartment. Surgeon's experience and operation volume did not affect these outcomes (P > .05).

Conclusions

Surgeons' ability to locate the ulnar nerve behind the posteromedial capsule using sole arthroscopic visualization, without external palpation, is poor. We recommend to proceed carefully when performing arthroscopic procedures in the posteromedial elbow, and identify and mobilize the ulnar nerve prior to any posteromedial capsular procedures.

Electrocautery in arthroscopic surgery: intra-articular fluid temperatures above 43 °C cause potential tissue damage

PURPOSE

The use of electrocautery during arthroscopy may heat intra-articular saline and subsequently damage intra- and extra-articular tissue. Newer electrocautery devices have the ability to measure the outflow fluid temperature and switch off before reaching a certain threshold; however, the scientific evidence establishing these temperature thresholds' potential for inadvertent damage is lacking. The aim of this study was to analyse current available literature on temperature thresholds for tissue damage after exposure to heated fluid and provide a recommendation for the maximum temperature of intra-articular fluid to prevent tissue damage.

METHODS

In February 2018, a systematic literature review was performed using the MEDLINE/PubMed and Embase databases. Inclusion was limited to studies investigating temperature thresholds for thermal damage to at least one of the tissues of interest: skin, bone, cartilage, soft tissues, and nerves. Studies not reporting specific temperature thresholds for thermal damage were excluded.

RESULTS

Twenty articles were selected for the final evaluation and data extraction. Varying temperature thresholds, based on the lowest reported temperature causing tissue damage, were found for the different tissues of interest: 44 °C for dermal tissues, between 47 and 50 °C for bony tissues, 50 °C for cartilage, between 43 and 55 °C for soft tissues, and 43 °C for nerves.

CONCLUSION

Based on the current literature, a temperature threshold for intra-articular fluid of 43 °C during an arthroscopic procedure is recommended to prevent tissue damage. Higher temperatures may cause damage to surrounding intra- and extra-articular tissues. The threshold for irreversible damage is likely to be higher. In clinical practise, one should be aware of possible heating of intra-articular fluid when using electrocautery and related risk of tissue damage.

LEVEL OF EVIDENCE

III.

Histologic Analysis of 2 Alternative Donor Sites of the Ipsilateral Elbow in the Treatment of Capitellar Osteochondritis Dissecans

PURPOSE

To compare the histologic features of the cartilage from the capitellum with 2 proposed alternative donor sites from the ipsilateral elbow in the treatment of capitellar osteochondritis dissecans (OCD): the nonarticulating part of the radial head and the nonarticulating lateral side of the olecranon tip.

METHODS

Ten human cadaveric elbow specimens with macroscopically normal articular surfaces were used to obtain 5-mm osteochondral grafts: 10 from the capitellum (60° anteriorly relative to the humeral shaft), 10 from the radial head (nonarticulating part at 80°), and 4 from the olecranon (lateral side of the olecranon tip). Grafts were fixated in formalin (4% formaldehyde), decalcified, and processed into standard 8-μm-thick hematoxylin and eosin-and Toluidine Blue-stained sections. These were assessed for cartilage thickness, shape of articular surface, and 13 histologic parameters of the International Cartilage Repair Society II. Olecranon scores were excluded from statistical analysis.

RESULTS

Mean cartilage thickness was 1.5 ± 0.22 mm at the capitellum; 1.3 ± 0.34 mm at the radial head; and 1.9 ± 1.0 mm at the olecranon. There was no difference in cartilage thickness between the capitellum and radial head (P = .062). All grafts demonstrated a convex articular surface. International Cartilage Repair Society II scores ranged from 82 to 100 for the capitellum, from 81 to 100 for the radial head, and from 67 to 87 for the olecranon tip. There was less chondrocyte clustering at the capitellum (84 ± 14) than in the radial head (94 ± 3.2; P = .019). Mid/deep zone assessment of the capitellum scored higher (97 ± 6.7) than the radial head (91 ± 4.6; P = .038).

CONCLUSIONS

This study demonstrates appropriate histologic similarities between the cartilage from the capitellum and 2 alternative donor sites of the ipsilateral elbow in the treatment of capitellar OCD: the nonarticulating part of the radial head and the nonarticulating lateral side of the olecranon tip.

CLINICAL RELEVANCE

From an histologic point of view, there seem to be no obstacles to use grafts from these alternative donor sites for reconstruction of the capitellum when performing osteochondral autologous transplantation.

Locating the ulnar nerve during elbow arthroscopy using palpation is only accurate proximal to the medial epicondyle

PURPOSE

Knowledge of ulnar nerve position is of utmost importance to avoid iatrogenic injury in elbow arthroscopy. The aim of this study was to determine how accurate surgeons are in locating the ulnar nerve after fluid extravasation has already occurred, and basing their localization solely on palpation of anatomical landmarks.

METHODS

Seven cadaveric elbows were used and seven experienced surgeons in elbow arthroscopy participated. An arthroscopic setting was simulated and fluids were pumped into the joint from the posterior compartment for 15 min. For each cadaveric elbow, one surgeon was asked to locate the ulnar nerve solely by palpation of the anatomical landmarks, and subsequently pin the ulnar nerve at two positions: within 5 cm proximal and another within 5 cm distal of a line connecting the medial epicondyle and the tip of the olecranon. Subsequently, the elbows were dissected using a standard medial elbow approach and the distances between the pins and ulnar nerve were measured.

RESULTS

The median distance between the ulnar nerve and the proximal pins was 0 mm (range 0-0 mm), and between the ulnar nerve and the distal pins was 2 mm (range 0-10 mm), showing a statistically significant difference (p = 0.009). All seven proximally placed pins (100%) transfixed the ulnar nerve versus two out of seven distally placed pins (29%) (p = 0.021).

CONCLUSIONS

In a setting simulating an already initiated arthroscopic procedure, the sole palpation of the anatomical landmarks allows experienced elbow surgeons to accurately locate the ulnar nerve only in its course proximal to the medial epicondyle (7/7, 100%), whereas a significantly reduced accuracy is documented when the same surgeons attempt to locate the nerve distal to the medial epicondyle (2/7, 29%; p = 0.021). Current findings support the establishment of a proximal anteromedial portal over a distal anteromedial portal to access the anterior compartment after tissue extravasation has occurred with regard to ulnar nerve safety.

Force measurement metrics for simulated elbow arthroscopy training

Background

Elbow arthroscopy is a difficult surgical technique. Objective metrics can be used to improve safe and effective training in elbow arthroscopy. Force exerted on the elbow tissue during arthroscopy can be a measure of safe tissue manipulation. The purpose of this study was to determine the force magnitude and force direction used by experts during arthroscopic elbow navigation in cadaveric specimens and assess their applicability in elbow arthroscopy training.

Methods

Two cadaveric elbows were mounted on a Force Measurement Table (FMT) that allowed 3-dimensional measurements (x-, y-, and z-plane) of the forces exerted on the elbow. Five experts in elbow arthroscopy performed arthroscopic navigation once in each of two cadaveric elbows, navigating through the posterior, posterolateral and anterior compartment in a standardized fashion with visualization of three to four anatomic landmarks per compartment. The total absolute force (F_abs) and force direction exerted (α and β) on the elbow during arthroscopy were recorded. α being the angle in the horizontal plane and β being the angle in the vertical plane. The 10th–90th percentiles of the data were used to set threshold levels for training.

Results

The median F_abs was 24 N (19 N – 30 N), 27 N (20 N – 33 N) and 29 N (23 N – 32 N) for the posterior, posterolateral and anterior compartment, respectively. The median α was - 29° (- 55° – 5°), - 23° (- 56° – -1°) and 4° (- 22° – -18°) for the posterior, posterolateral and anterior compartment, respectively. The median β was - 71° (- 80° – -65°), - 76° (- 86° – -69°) and - 75° (- 81° – -71°) for the posterior, posterolateral and anterior compartment, respectively.

Conclusion

Expert data on force magnitude and force direction exerted on the elbow during arthroscopic navigation in cadaveric specimens were collected. The proposed maximum allowable force of 30 N (smallest 90th percentile of F_abs) exerted on the elbow tissue, and the 10th–90th percentile range of the force directions (α and β) for each compartment may be used to provide objective feedback during arthroscopic skills training.

Nerve injuries do occur in elbow arthroscopy

PURPOSE

The purpose is to create more awareness as well as emphasize the risk of permanent nerve injury as a complication of elbow arthroscopy.

METHODS

Patients who underwent elbow arthroscopy complicated by permanent nerve injury were retrospectively collected. Patients were collected using two strategies: (1) by word-of-mouth throughout the Dutch Society of Shoulder and Elbow Surgery, and the Leiden University Nerve Centre, and (2) approaching two medical liability insurance companies. Medical records were reviewed to determine patient characteristics, disease history and postoperative course. Surgical records were reviewed to determine surgical details.

RESULTS

A total of eight patients were collected, four men and four women, ageing 21-54 years. In five out of eight patients (62.5%), the ulnar nerve was affected; in the remaining three patients (37.5%), the radial nerve was involved. Possible causes for nerve injury varied among patients, such as portal placement and the use of motorized instruments.

CONCLUSIONS

A case series on permanent nerve injury as a complication of elbow arthroscopy is presented. Reporting on this sequel in the literature is little, however, its risk is not to be underestimated. This study emphasizes that permanent nerve injury is a complication of elbow arthroscopy, concurrently increasing awareness and thereby possibly aiding to prevention.

LEVEL OF EVIDENCE

IV, case series.

Tips to avoid nerve injury in elbow arthroscopy

Elbow arthroscopy is a technical challenging surgical procedure because of close proximity of neurovascular structures and the limited articular working space. With the rising number of elbow arthroscopies being performed nowadays due to an increasing number of surgeons performing this procedure and a broader range of indications, a rise in complications is foreseen. With this editorial we hope to create awareness of possible complications of elbow arthroscopy, particularly nerve injuries, and provide a guideline to avoid complications during elbow arthroscopy.

Pneumomediastinum and soft tissue emphysema in pediatric hanging

Postmortem computed tomography (CT) is increasingly being used as a tool in forensic pathology. The exact value of postmortem imaging in detecting specific conditions has not yet been established, but in specific cases, it can be used as a diagnostic tool demonstrating findings that remain undetected during autopsy, as in this case. Pneumomediastinum and soft tissue emphysema were detected with postmortem CT in a 3-year-old girl after hanging. It was not found during autopsy. This radiological finding matches 3 adult cases previously described. It is assumed that in this case, the first reported in a child, hanging was the most likely cause as well. In the adult cases, it was interpreted as a vital sign; the person must have been alive to create a pressure gradient causing rupture of the alveoli. This case demonstrates one of the added values of postmortem imaging, the possibility of demonstrating findings that remain undetected during autopsy.