Assessment and decision making in the unstable elbow: management of simple dislocations

Arthroscopic assessment for lateral collateral ligament complex deficiency of the elbow: a cadaveric study

PURPOSE

To evaluate whether elbow instability due to lateral collateral ligament complex injury can be assessed reliably through arthroscopy.

METHODS

Eight fresh human cadaveric elbows were placed in a simulated lateral decubitus position. The radiocapitellar joint (RCJ) gap and ulnohumeral joint (UHJ) gap (mm) were measured with different sizes of probes from the posterolateral viewing portal. The elbow was 90 degrees flexed with neutral forearm rotation for RCJ gap measurement and 30 degrees flexed with full supination for UHJ gap measurement. Sequential testing was performed from Stage 0 to Stage 3 (Stage 0: intact; Stage 1: the release of the anterior 1/3 LCL complex; Stage 2: the release of the anterior two thirds of the LCL complex; and Stage 3: the release of the entire LCL complex) on each specimen. The mean gap of RCJ and lateral UHJ was used for the comparison between stages with the intact elbow.

RESULTS

The mean RCJ gap distance in Stage 2 and Stage 3 was significantly increased compared to that in Stage 0 (Stage 0 vs. Stage 2: P = .008; Stage 0 vs. Stage 3: P = .010). The mean UHJ gap distance of Stage 1, Stage 2, and Stage 3 was significantly increased compared to that in Stage 0 (Stage 0 vs. Stage 1: P = 0.025; Stage 0 vs. Stage 2: P = .010; Stage 0 vs. Stage 3: P = .011). In contrast, the release of the anterior 1/3 of the LCL complex (Stage 1) was not significantly increased compared to the mean joint gap distance of RCJ (P = .157).

CONCLUSION

Arthroscopic measurement of joint gap widening in RCJ and UHJ is a reliable assessment method to detect LCL complex deficiency that involves the anterior two thirds or more.

Acute Dislocation of the Elbow: An All-Arthroscopic Repair of the Lateral Ligament Complex

The elbow is one of the most commonly dislocated joints. While conservative management is frequently performed for simple elbow dislocations, the importance of primary surgical treatment is still undetermined. However, promising results have been reached after surgical repair. We propose an arthroscopic surgical repair of the lateral ligament complex (LCL), performed with a horizontal suture and 2 Fibertak Knotless implants (Arthrex) placed on the LCL origin, one anterior and the other posterior. Operative treatment should be performed in patients with moderate and gross elbow laxity to avoid post-traumatic sequelae and decrease revision rates. Arthroscopic techniques create fewer complications. This procedure allows one to address intra-articular elbow joint pathology with less chance of wound complications and the ability to use bone anchors if desired.

[Ligamentous elbow injuries-When is surgical treatment still indicated?]

The elbow joint is a hinge-type synovial joint and is the second most frequently dislocated joint in adults and the most frequently dislocated joint in children. To find the right treatment options a precise understanding of the injury pattern, anatomy, biomechanics and pathology (simple vs. complex dislocation) is essential for a good reconstruction of the function and to prevent chronic instability and pain. The differentiation between acute and chronic instability gives another variation in the treatment plan. According to the latest literature there are clear indications for surgery of a complex elbow dislocation, whereas for simple dislocations conservative treatment is preferentially recommended; however, when is the surgical treatment of a ligamentous elbow dislocation (still) indicated?

Musculoskeletal simulation of elbow stability for common injury patterns

Elbow stability is derived from a combination of muscular, ligamentous, and bony structures. After an elbow trauma the stability of the joint is an important decision criterion for the subsequent treatment. The decision regarding nonoperative/operative care depends mostly on subjective assessments of medical experts. Therefore, the aim of this study is to use musculoskeletal simulations as an objective assessment tool to investigate the extent to which failure of different stabilizers affects the elbow stability and how these observations correspond to the assessment from clinical practice. A musculoskeletal elbow simulation model was developed for this aim. To investigate the stability of the elbow, varus/valgus moments were applied under 0°, 45°, and 90° flexion while the respective cubital angle was analyzed. This was performed for nine different injury scenarios, which were also evaluated for stability by clinical experts. With the results, it can be determined by which injury pattern and under which flexion angle the elbow stability is impaired regarding varus/valgus moments. The scenario with a complete failure of the medial and lateral ligaments and a fracture of the radial head was identified as having the greatest instability. The study presented a numerical determination of elbow stability against varus/valgus moments regarding clinical injury patterns, as well as a comparison of the numerical outcome with experience gained in clinical practice. The numerical predictions agree well with the assessments of the clinical specialists. Thus, the results from musculoskeletal simulation can make an important contribution to a more objective assessment of the elbow stability.

Four-dimensional computed tomography scan for dynamic elbow disorders: recommendations for clinical utility

BACKGROUND

Four-dimensional computed tomography (4D CT) is rapidly emerging as a diagnostic tool for the investigation of dynamic upper limb disorders. Dynamic elbow pathologies are challenging to diagnose, and at present, limitations exist in current imaging modalities.

OBJECTIVE

We aimed to assess the clinical utility of 4D CT in detecting potential dynamic elbow disorders.

METHODS

Twenty-eight elbow joints from 26 patients with symptoms of dynamic elbow pathology were included in this study. They were first assessed by a senior orthopedic surgeon with subsequent qualitative data obtained via a Siemens Force Dual Source CT scanner (Erlangen, Germany), producing two- and three-dimensional "static" images and 4D dynamic "movie" images for assessment in each clinical scenario. Clinical assessment before and after scan was compared.

RESULTS

Use of 4D CT scan resulted in a change of diagnosis in 16 cases (57.14%). This included a change in primary diagnosis in 2 cases (7.14%) and secondary diagnosis in 14 cases (50%). In 25 cases (89.29%), the 4D CT scan allowed us to understand the pathological anatomy in greater detail which led to a change in the management plan of 15 cases (53.57%).

CONCLUSION

4D CT is a promising diagnostic tool in the management of dynamic elbow disorders and may be considered in clinical practice. Future studies need to compare it with other diagnostic modalities such as three-dimensional CT.

Dislocations of the elbow - An instructional review

Dislocations of the elbow require recognition of the injury pattern followed by adequate treatment to allow early mobilisation. Not every injury requires surgery but if surgery is undertaken all structures providing stability should be addressed, including fractures, medial and lateral ligament insertion and the radial head. The current concepts of biomechanical modelling are addressed and surgical implications discussed.

Arthroscopic Diagnosis of Posterolateral Rotatory Instability of the Elbow

Posterolateral rotatory instability (PLRI) is the most common form of symptomatic acute and chronic elbow instability. Diagnosis is usually made using a combination of clinical tests and imaging modalities; however, in more subtle forms of instability, these measures may be equivocal. Arthroscopy is a valuable adjunct for diagnosis and treatment of PLRI. It allows direct appreciation of the instability process, quantification of the degree of instability, and identification of concurrent associated pathology. The aim of this technique article is to report a series of reproducible arthroscopic tests used for diagnosis of PLRI with examples of normal and pathologic arthroscopic findings.

Treatment of posteromedial and posterolateral dislocation of the acute unstable elbow joint: a strategic approach

BACKGROUND

The purpose of this study was to evaluate the different treatment strategies for posterolateral and posteromedial elbow dislocation.

METHODS

The study enrolled 21 patients with unstable simple elbow dislocation including 16 cases of posterolateral dislocation (PLDL) and 5 cases of posteromedial dislocation (PMDL). In patients with PLDL, the medial side was evaluated and repaired first, followed by the lateral side. In patients with PMDL, the lateral side was repaired first, followed by the medial side according to residual instability.

RESULTS

Among the 16 cases of unstable PLDL, 7 of 9 presenting with complex combined tear of the ulnar collateral ligament (UCL) and flexor muscle on magnetic resonance imaging showed abnormality on valgus stress testing and UCL repair. Three of 7 cases required additional lateral collateral ligament complex (LCLC) repair. Two of 9 cases showing medial complex dual lesions had normal findings on valgus stress testing and were treated only with LCLC repair. Seven of 16 cases without medial complex dual lesion had normal findings on valgus stress testing, and only LCLC repair was performed. All 5 cases of unstable PMDL showed distraction-type LCLC injury on magnetic resonance imaging and required no additional UCL repair after LCLC repair. There were no cases of recurrent instability following this treatment algorithm.

CONCLUSIONS

In unstable elbow dislocation, PLDL and PMDL are caused by different mechanisms following damage to different structures. Therefore, different strategies are needed to ameliorate the dislocation and instability.