A cadaveric study of the three different palpation-guided techniques for glenohumeral joint injections

BACKGROUND

It is not known whether an anterior, posterior or superior approach using the Neviaser portal is more accurate for glenohumeral joint injections. The aim of this study was to evaluate the accuracy of the palpation-guided technique and compare the three different approaches.

METHODS

Palpation-guided glenohumeral joint injections were performed in 48 shoulders (24 cadavers) by two operators. Each shoulder was injected by three different approaches with a different coloured latex solution. The three approaches included the anterior, posterior and superior methods. The accuracy and location of unsuccessful injections were assessed through dissection of the shoulders.

RESULTS

Posterior injections were the most successful with an accuracy rate of 89.6%, followed by anterior injections (75%) and superior injections (54.2%). Both posterior (p = 0.0001) and anterior injections (p = 0.03) were statistically significantly more accurate than superior injections. The most common failure mode was an intratendinous or intramuscular injection, which occurred most frequently with a superior approach.

CONCLUSIONS

Use of a superior approach through the Neviaser portal for the palpation-guided technique for glenohumeral joint injections showed a statistically significant inferior accuracy when compared to both the posterior and anterior approaches and is therefore not recommended. Posterior approached injections were the most accurate.

Stress reactions and fractures around the elbow in athletes

Stress fractures of the upper limb affect athletes from a wide range of sports. Athletes involved in throwing sports are particularly susceptible along with athletes from sports involving high repetitive and compressive loads such as gymnastics. Diagnosis can be made from clinical history, examination and radiography in some cases however MRI imaging is often required for definitive diagnosis. The mainstay of management is rest and activity modification however advanced pathology often requires surgical management for successful resolution and return to play. In the elbow, the bones susceptible to excessive stress in sport are the distal humerus, the olecranon process of the ulna, the coronoid process of the ulna, the sublime tubercle and the radial head. In immature patients, medial epicondyle apophysis is the most common location. The article presents a narrative review of the literature.

Single versus dual orthogonal plating for comminuted midshaft clavicle fractures: a biomechanics study

BACKGROUND

Dual orthogonal plating of clavicle fractures may provide greater stiffness and strength than unilateral plate constructs and allow the use of lower-profile plates. We aim to biomechanically compare three clavicle plating constructs in a comminuted clavicle fracture model.

METHOD

Fifteen clavicle sawbones were osteotomised, simulating a comminuted midshaft fracture and allocated to either: group 1, single superior plate (3.5 mm superior plate); group 2, combination plating (3.5 mm superior plate, 2.8 mm anterior plate) and group 3, dual mini-plates (two 2.8-mm orthogonal mini-plates). Specimens were biomechanically tested under torsion and cantilever bending. Construct stiffness (Nm/degree) and load to failure (Nm) were measured.

RESULTS

Group 2 had higher torsional (0.70 vs. 0.60 Nm/deg, p = 0.017) and cantilever bending stiffness (0.61 vs. 0.51 Nm/deg, p = 0.025) than group 1. Group 3 had lower cantilever bending stiffness (0.39 vs. 0.51 Nm/deg, p < 0.004) and load to failure (40.87 vs. 54.84 Nm, p < 0.01) than group 1. All dual plate constructs that catastrophically failed did so from fracture at the lateral ends of the plates. Single plate constructs failed due to plate bending.

CONCLUSION

Dual orthogonal fixation with mini-plates demonstrated lower stiffness and strength than traditional superior plating. The addition of an anterior mini-plate to a traditional superior plating improved construct stiffness and may have a role in patients seeking early return to activity.

LEVEL OF EVIDENCE

Basic science biomechanical study.

Isolated Proximal Radioulnar Joint Instability: Anatomy, Clinical Presentation, and Current Treatment Options

Isolated proximal radioulnar joint instability is an uncommon and often challenging problem that may manifest as recurrent instability of the proximal aspect of the radius, usually during forearm pronation and supination. Instability is due to deficiency of the stabilizing structures around the proximal aspect of the radius, and biomechanical studies have highlighted the importance of the annular ligament and the interosseous membrane in both transverse and longitudinal plane stability. Reconstruction of the stabilizing structures around the radial head often is indicated in cases of recurrent instability and includes joint-preserving procedures such as annular ligament reconstruction, proximal ulnar osteotomy, and interosseous membrane reconstruction. Rarely, salvage procedures such as interpositional arthroplasty or 1-bone forearm reconstruction are necessary. A thorough understanding of the anatomic structures that stabilize the proximal aspect of the radius and the complexities of forearm biomechanics is required in order to successfully diagnose and manage this condition.

Innervation of the acromioclavicular joint by the suprascapular nerve

BACKGROUND

The suprascapular nerve is largely responsible for the majority of the sensory innervation of the acromioclavicular joint. In this anatomical study, we describe, in detail, the anatomy of the sensory innervation of the acromioclavicular joint by the branches of the suprascapular nerve.

METHODS

Twenty-seven shoulders from 17 cadaveric specimens were carefully dissected to identify the course of the suprascapular nerve, with the main focus being on the sensory innervation of the acromioclavicular joint. Nine specific measurements of the acromioclavicular joint sensory nerves were made of each shoulder in relation to distinct anatomical landmarks to determine the mean location and course of these nerves.

RESULTS

In all 27 shoulders (100%), a sensory branch to the acromioclavicular joint with a proximal origin from the suprascapular nerve could be depicted ("first sensory branch"). The mean length of this branch was 4.3 cm (range: 3.3-5.3 cm). In 14 shoulders (52%), a further sensory branch of the suprascapular nerve innervating the posterior acromioclavicular joint capsule could be identified ("second sensory branch").

DISCUSSION

A detailed anatomical description of the sensory innervation of the acromioclavicular joint from suprascapular nerve branches was performed, which can potentially aid in the development of more focused anesthetic blockades and acromioclavicular joint denervation procedures.

Medial Femoral Trochlea Graft for Scaphoid Waist Nonunion: A Case Report and Review of the Literature

The medial femoral trochlea (MFT) of the knee is a donor site for convex osteochondral vascularized bone that has been used for the salvage of fractures of the proximal pole of the scaphoid. Chronic nonunited fractures of the scaphoid may lead to a sequence of degenerative change often referred to as scaphoid nonunion advance collapse. The vascularized MFT osteochondral graft has been reported as a salvage procedure for fractures of the proximal pole of the scaphoid, in situations where fixation is not an option. In this "Special review," we describe the technique of free vascularized MFT graft in a case in which the nonunited scaphoid fracture was associated with segmental loss of the articular surface of the scaphoid waist. Given the likely progression of arthritis, if left untreated, we elected to treat this by replacing the lost articular surface using a vascularized intercalary osteochondral MFT graft between the nonunited scaphoid segments.

Arthroscopic Knotless Repair of Complete Full-Thickness Tears of the Subscapularis Tendon Through a Single Portal

Arthroscopic repair of subscapularis tendon tears has shown to be a reliable and reproducible technique and is now considered the gold standard method over open repair. However, most arthroscopic techniques use several working portals and the procedure can be technically challenging and time-consuming, especially when knot-tying is required and when multiple anchors are used. Recently, single-portal knotless techniques have been popularized for upper-third lesions (e.g. Lafosse type 1 or 2 tears). Here, we describe a technique of repairing complete tears of the subscapularis tendon (Lafosse type 3 and 4) using knotless suture anchors through a single portal. This technique is quick and allows a safe anatomic footprint repair to the lesser tuberosity.

Surgical management of chronic high-grade acromioclavicular joint dislocations: a systematic review

BACKGROUND

To date, no gold-standard technique exists for the treatment of chronic acromioclavicular joint (ACJ) instability. We systematically reviewed the clinical results of 3 main categories of ACJ reconstruction for high-grade chronic instability.

METHODS

A literature search was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The inclusion criteria were clinical studies involving patients with ACJ instability (Rockwood grades III-VI) for at least 6 weeks, managed with ACJ stabilization, with a minimum 1-year follow-up. Depending on the surgical technique, patients were divided into 1 of 3 groups: nonbiological fixation between the coracoid and clavicle, for example, suture loops and synthetic ligaments (group 1); biological reconstruction of the coracoclavicular ligaments, for example, allograft or autograft ligament reconstruction (group 2); and ligament and/or tendon transfer, for example, the Weaver-Dunn procedure (group 3). Patient demographic characteristics, functional scores, radiographic outcomes, and complications were compared.

RESULTS

Two independent investigators reviewed 960 articles. A total of 27 studies met the inclusion criteria, comprising 590 patients divided into 1 of 3 groups. The complication rates were similar among the 3 groups: 15% for nonbiological fixation, 15% for biological reconstruction, and 17% for ligament and/or tendon transfer, with failure rates of 8%, 7%, and 5%, respectively. In terms of functional results, the mean Constant score was 87.2 points for nonbiological fixation (n = 89), 92.4 points for biological reconstruction (n = 86), and 87.4 points for ligament and/or tendon transfer (n = 49).

CONCLUSION

On comparison of the results of 3 different ACJ reconstruction methods, all techniques showed similar complication rates. Among the level II studies, ACJ reconstruction with a tendon graft showed superior results.

The Twist X-Ray: A Novel Test for Dynamic Scapholunate Instability

Background  Scapholunate instability (SLI) is the most common form of carpal instability. Early detection of SLI is imperative as early reconstructive procedures can potentially prevent the natural history of progressive degenerative arthritis. After wrist arthroscopy, magnetic resonance imaging (MRI) remains the next best noninvasive diagnostic option; however, access still remains costly and is often limited in many health care systems worldwide. In this article, we describe a novel device that allows for dynamic X-rays to be taken, accentuating the scapholunate (SL) widening. Description of Technique  Twist X-ray views are generated by the patient clenching a device that combines the standard clenched fist views with ulnar deviation and supination. The test is easy to perform and functions by combining a higher grip force with the ulnar deviation and pronation effects of the extensor carpi ulnaris tendon, thus accentuating the SL gap in dynamic instability. Patients and Methods  We present a series of four patients with dynamic SLI and compare the findings of the Twist X-rays with conventional wrist X-rays series, including standard anteroposterior, lateral, radial, and ulna deviation, clenched fist, and pencil grip views. Results  In all the four patients, there was substantial dynamic SL widening. The SL interval increased from a mean of 1.8 mm (range: 1.5-2.8) on posteroanterior X-rays to 6.3 mm (range: 4.6-8.2) with the Twist views. Interestingly, on the pencil grip view, the mean widening was only 1.5 mm (range: 1-2.8 mm). Conclusion  The authors describe a novel device that allows for improved detection of dynamic SL ligament instability when performing stress X-ray views of the wrist. Level of Evidence  This is a Level IV study.

Quantitative analysis of in-vivo thumb carpometacarpal joint kinematics using four-dimensional computed tomography

The purpose of this study was to define the normal thumb carpometacarpal joint kinematics in-vivo during opposition and abduction using four-dimensional computed-tomography in four volunteers. Movement of the metacarpal relative to the trapezium was quantified using both Euler and helical axis representations. Articular surface contact patterns were also analysed. The overall axis of rotation for the movement of opposition and abduction passes through the trapezium and the base of the proximal phalanx, respectively. An abrupt change in instantaneous axis of rotation at terminal opposition was found. Ligament modelling shows dorsoradial ligament becomes tauter towards terminal opposition, whereas anterior oblique ligament becomes more slack. These results support the existence of the 'screw-home' pivot at terminal opposition and the importance of the dorsoradial ligament for stability in this position. The normal reference set in this study can help establish a diagnostic tool for subtle carpometacarpal instability, or for evaluating efficacy of surgery.

Nonspanning Total Wrist Arthrodesis with a Low-Profile Locking Plate

Purpose  This study aims to compare the outcomes and complications of our technique for nonspanning total wrist arthrodesis using a locking plate with the standard carpometacarpal spanning technique. Methods  A retrospective review of charts was performed to identify patients who underwent total wrist arthrodesis by the senior author (S.W.W.). We compared the outcomes of 15 cases of nonspanning wrist fusion with a 2.4/2.7 mm locking T plate to 11 cases of spanning wrist fusion with a 2.7/3.5 mm locking compression plate. Minimum follow-up was 3 months. Indications for fusion included rheumatoid arthritis, posttraumatic arthritis, Kienböck's disease, primary osteoarthritis, juvenile inflammatory arthropathy, psoriasis, brachial plexopathy, failed hemi or total wrist arthroplasty, failed four-corner fusion, and failed proximal row carpectomy. The primary outcome was fusion. Secondary outcomes included time to union, patient-rated wrist evaluation score, numerical rating scale pain score, grip strength, and complications. Results  All the wrists got fused. There were no significant differences in objective and subjective outcomes between cohorts. There were three complications (27%) in the spanning group, including tendon rupture and peri-implant fracture at the third metacarpal. This was compared with three complications (20%) in the nonspanning group, consisting of hardware removal. Discussion  We achieved similar fusion rates employing both spanning and nonspanning total wrist arthrodesis techniques, without necessitating carpometacarpal arthrodesis in the latter. Complications associated with our method were comparably less severe than those reported in the literature. We advocate nonspanning arthrodesis as an alternative method for total wrist fusion with a high union rate and minimal risk of complications at the carpometacarpal joint. Level of Evidence  Therapeutic level IV.

Scaphoid Fracture Fixation in a Nonunion Model: A Biomechanical Study Comparing 3 Types of Fixation

PURPOSE

Union of a scaphoid fracture after fixation is influenced by various factors, one of which is fracture stability. This study aims to compare the biomechanical stability of 3 different types of scaphoid fracture fixation in a scaphoid nonunion model.

METHODS

Thirty cadaveric scaphoid specimens were assigned to one of 3 different fixation groups: (1) single 3.0-mm compression screw, (2) two 2.2-mm screws, and (3) scaphoid plate. A 3-mm volar wedge osteotomy was created at the scaphoid waist to simulate a nonunion model. The primary outcome measure was load to failure, whereas secondary outcome measures were load to 2-mm displacement, energy absorbed, stiffness, and mode of failure, recorded by video and retrieval analysis.

RESULTS

There was a significantly lower load to failure in the single screw construct compared with that in the double screw (mean difference 187.2 N) and plate fixation constructs (mean difference 150.7 N). The mean load to 2-mm displacement in the single screw construct (91.5 N) was also significantly lower than that in the double screw (181.8 N) and plate fixation constructs (197.2 N). There was a significantly lower stiffness with the single screw fixation compared with that of the double screws (mean difference 85.4 N/mm), and lower energy absorbed with single screws when compared with that of double screws (mean difference 386.5 mJ) and when compared with plate fixation (mean difference 270.8 mJ).

CONCLUSIONS

In this biomechanical study comparing fixation methods using a model of scaphoid nonunion with bone loss, we found that double screws or plate fixation demonstrated significantly greater stability, stiffness, and energy absorption when compared with a single compression screw. We found no discernible differences between double screw fixation and the plate groups.

CLINICAL RELEVANCE

The use of double screws or plate fixation in a nonunion setting may allow accelerated rehabilitation without compromise to fracture stability.

Arthroscopic Repair of the Lateral Ulnar Collateral Ligament of the Elbow Using a Knotless Suture Anchor

The lateral collateral ligament (LCL) complex of the elbow plays a crucial role in the stability of the elbow joint, especially to varus loads. Deficiency of particularly the lateral ulnar collateral component of the LCL can lead to chronic posterolateral rotatory instability, which can be functionally debilitating and can lead to a rapid onset of early degenerative arthritis. Commonly, in the setting of acute rupture of the LCL, the ligament is repaired using an open technique with suture anchor fixation to the lateral epicondyle insertion point. However, with advancing arthroscopic techniques, it has become possible to repair the LCL arthroscopically. We present a relatively simple method for an all-arthroscopic repair of the LCL to the humerus using a knotless suture anchor technique.

Fixation of Ultrasmall Proximal Pole Scaphoid Fractures Using Bioabsorbable Osteochondral Fixation Nails

Surgical treatment of ultrasmall proximal pole scaphoid fractures poses a number of challenges. The fragment may be too small to fix with conventional headless screw fixation owing to the high risk of fragmentation upon insertion. However, excision of the fragment risks compromising the scapholunate ligament complex and also exposes the radioscaphoid joint to potential degenerative changes. Under these circumstances, we describe the use of bioabsorbable osteochondral fixation nails that allows stable low-profile fixation while minimizing the risk of fracturing the proximal pole.

Interobserver and intraobserver variability of glenoid track measurements

BACKGROUND

A method of assessing combined glenoid and humeral bone loss in traumatic shoulder instability with an associated treatment protocol was recently published. The aim of this study was to investigate its reliability and reproducibility.

METHODS

Seventy-one patients with unilateral anteroinferior shoulder instability underwent computed tomography scans, from which 3-dimensional images were derived. En face views of both glenoid fossae and with 3 views of the humeral head were provided to 4 assessors to determine interobserver reliability. From these measurements, the shoulder was assigned a treatment classification. Two observers repeated their assessments 1 month later to determine intraobserver reliability. For each measurement, the mean coefficient of variability was calculated.

RESULTS

Assessment of glenoid bone loss showed good interobserver (4 observers agreeing in 90.1% of cases) and also good intraobserver agreement (94% and 96%). There was a poor level of interobserver reliability regarding the on-track or off-track classification (72%). Intraobserver reliability for this measurement was less variable (90% and 80%). There was a poor level of agreement between observers (65%) regarding treatment classification. The coefficient of variability for the Hill-Sachs lesion measured 19.2%, indicating a high level of variability for this measurement compared with <4% for all other measures.

CONCLUSION

Linear bone loss on the glenoid can be measured reliably and reproducibly; however, evaluation of Hill-Sachs lesions demonstrates a high level of variability, and poor interobserver reliability.

Use of a Bone Graft Drill Harvester to Create the Fenestration During Arthroscopic Ulnohumeral Arthroplasty

The Outerbridge-Kashiwagi procedure, or ulnohumeral arthroplasty, was described in 1978 as a method of treating elbow arthritis by creating a fenestration in the olecranon fossa. This fenestration diminishes the likelihood of recurrent spurs in the olecranon fossa and coronoid fossa, without loss of structural bony strength. Arthroscopic techniques have now been developed to perform this procedure. We describe an efficient method of creating the fenestration between the olecranon fossa and coronoid fossa during an arthroscopic ulnohumeral arthroplasty, or Outerbridge-Kashiwagi procedure, that also reduces the amount of residual bone debris produced during the resection.

Biomechanical Analysis of Scapholunate Ligament Repair Techniques

PURPOSE

To evaluate the biomechanical properties of 3 scapholunate repair techniques.

METHODS

In 51 cadavers, the scapholunate ligament was exposed through a dorsal approach, incised at its scaphoid insertion, and repaired using 1 of 3 techniques: 2 single-loaded suture anchors, 2 double-loaded suture anchors, or 2 transosseous sutures. Twenty-four repaired specimens underwent load to failure (LTF) testing using tensile distraction on a servo-hydraulic machine. Twenty-seven specimens underwent cyclical testing to measure gap formation at the scapholunate joint.

RESULTS

The mode of failure was suture pullout through the substance of the ligament in 22 specimens, failure at the bone suture interface in 1, and anchor pullout in 1. Double-loaded anchor repairs demonstrated a significantly higher mean ultimate LTF compared with single-loaded anchor (91 N vs 35 N) and transosseous (91 N vs 60 N) repairs. Transosseous repairs demonstrated a higher mean ultimate LTF compared with single-loaded suture repairs (60 N vs 35 N). After 300 cycles, the average gap for the transosseous repair group was double that for the single- and double-loaded repairs, although not statistically significant.

CONCLUSIONS

Primary scapholunate ligament repairs using double-loaded suture anchors demonstrated significantly higher strength compared with single-loaded anchors and transosseous repairs. On cyclic loading, transosseous repairs demonstrated the greatest gap formation with no measurable difference between single- and double-loaded repairs.

CLINICAL RELEVANCE

In a cadaveric model for primary repairs, double-loaded suture anchors demonstrated the highest LTF and offer a similar but unproven performance in vivo.

Failure of the lesser tuberosity osteotomy after total shoulder arthroplasty

BACKGROUND

Lesser tuberosity osteotomy (LTO) as an approach during total shoulder arthroplasty (TSA) is a reliable technique with strong biomechanical fixation and a low failure rate. Complications have been infrequently reported in the literature.

METHODS

We report a case series of 5 patients who sustained failure of the LTO repair after primary TSA. The data on the patient demographic characteristics, surgical technique, postoperative care, revision surgery, and clinical outcomes are reported.

RESULTS

The mean age of the 5 patients was 52 years, all patients were men, and the mean body mass index was 28 kg/m(2). They were followed up for a mean of 29 months (range, 24-38 months). The mean time from initial TSA to diagnosis of LTO failure was 9 weeks (range, 5-12 weeks). Two patients reported no trauma, 2 had minor trauma (using a pulley, rolling over in bed), and 1 sustained a fall. At the latest follow-up, the mean visual analog scale; Single Assessment Numeric Evaluation; University of California, Los Angeles; and American Shoulder and Elbow Surgeons scores were 4 (range, 0-6), 48 (range, 20-70), 19 (range, 11-22), and 63 (range, 48-83), respectively. Only 1 patient required no additional procedures beyond the revision LTO repair. Another patient required a second revision LTO repair. The remaining 3 patients either underwent or were recommended to undergo reverse arthroplasty.

CONCLUSION

Failure of the LTO repair after TSA may possibly be an under-reported complication that is associated with poor clinical outcomes and limited options for revision surgery. In patients with a high risk of LTO failure, considerations should be made to augment the LTO repair during the index TSA procedure.

Comparisons of preoperative three-dimensional planning and surgical reconstruction in primary cementless total hip arthroplasty

Reconstruction of important parameters such as femoral offset and torsion is inaccurate, when templating is based on plain x-rays. We evaluate intraoperative reproducibility of pre-operative CT-based 3D-templating in a consecutive series of 50 patients undergoing primary cementless THA through an anterior approach. Pre-operative planning was compared to a postoperative CT scan by image fusion. The implant size was correctly predicted in 100% of the stems, 94% of the cups and 88% of the heads (length). The difference between the planned and the postoperative leg length was 0.3 + 2.3 mm. Values for overall offset, femoral anteversion, cup inclination and anteversion were 1.4 mm ± 3.1, 0.6° ± 3.3°, -0.4° ± 5° and 6.9° ± 11.4°, respectively. This planning allows accurate implant size prediction. Stem position and cup inclination are accurately reproducible.

Carpal fractures

Carpal fractures are exceedingly rare clinical entities and are often associated with concomitant injuries. In this review, we focus on fractures of the carpus, excluding the scaphoid, and provide an update on the current consensus as to mechanism, diagnosis, management, outcomes, and complications after such injuries.